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Sample records for rsa contour reduction

  1. Selective radiofrequency therapy as a non-invasive approach for contactless body contouring and circumferential reduction.

    Science.gov (United States)

    Fajkošová, Kateřina; Machovcová, Alena; Onder, Meltem; Fritz, Klaus

    2014-03-01

    In this study, the efficacy of non-contact, selective radiofrequency (RF) were evaluated for body contouring as non-invasive fat and circumferential reduction of the abdomen. 40 healthy (36 female, 4 male) subjects showing significant volume of subcutaneous fat tissue on the abdomen and waistline were included. Once a week for 30 minutes, 4 sessions were performed. The applicator was placed on a supplied spacer covering the treatment area. Maximum power was 200W, which induced heat in the fat and connective tissue layer. The homogeneity of heat distribution and temperature of the skin surface were controlled. The circumferential reduction was measured at the baseline and after the last treatment. The photographs and adverse effects were recorded. Participants completed the self-evaluation questionnaires and rated their level of satisfaction. All subjects tolerated the treatments well. The only side effect was mild to moderate erythema. 35 subjects finished the protocol as planned and 5 subjects dropped off due to events not related to the study. 32 subjects had a 1-13 cm decrease in abdominal circumference and 3 subjects did not show significant response (0-1 cm). Most likely, a very thin fat layer was the reason for lack of response (the non-responding group was the thinnest patient group). No significant differences were found between men and women. The average decrease of 4.93 cm was calculated as a result of circumferential reduction statistical evidence. This study demonstrates that the selective RF system designed for contactless deep tissue heating is a painless, safe, and effective treatment for non-surgical body contouring and circumferential fat reduction.

  2. Motion detection, noise reduction, texture suppression, and contour enhancement by spatiotemporal Gabor filters with surround inhibition.

    Science.gov (United States)

    Petkov, Nicolai; Subramanian, Easwar

    2007-12-01

    We study the orientation and speed tuning properties of spatiotemporal three-dimensional (3D) Gabor and motion energy filters as models of time-dependent receptive fields of simple and complex cells in the primary visual cortex (V1). We augment the motion energy operator with surround suppression to model the inhibitory effect of stimuli outside the classical receptive field. We show that spatiotemporal integration and surround suppression lead to substantial noise reduction. We propose an effective and straightforward motion detection computation that uses the population code of a set of motion energy filters tuned to different velocities. We also show that surround inhibition leads to suppression of texture and thus improves the visibility of object contours and facilitates figure/ground segregation and the detection and recognition of objects.

  3. New Weak Keys in RSA

    Institute of Scientific and Technical Information of China (English)

    WANG Baocang; LIU Shuanggen; HU Yupu

    2006-01-01

    The security of the RSA system with the prime pairs of some special form is investigated. A new special-purpose algorithm for factoring RSA numbers is proposed. The basic idea of the method is to factor RSA numbers by factoring a well-chosen quadratic polynomial with integral coefficients. When viewed as a general-purpose algorithm, the new algorithm has a high computational complexity. It is shown that the RSA number n=pq can be easily factored if p and q have the special form of p=as+b, q=cs+d, where a, b, c, d are relatively small numbers. Such prime pairs (p, q) are the weak keys of RSA, so when we generate RSA modulus, we should avoid using such prime pairs (p, q).

  4. Simple Backdoors on RSA Modulus by Using RSA Vulnerability

    Science.gov (United States)

    Sun, Hung-Min; Wu, Mu-En; Yang, Cheng-Ta

    This investigation proposes two methods for embedding backdoors in the RSA modulus N=pq rather than in the public exponent e. This strategy not only permits manufacturers to embed backdoors in an RSA system, but also allows users to choose any desired public exponent, such as e=216+1, to ensure efficient encryption. This work utilizes lattice attack and exhaustive attack to embed backdoors in two proposed methods, called RSASBLT and RSASBES, respectively. Both approaches involve straightforward steps, making their running time roughly the same as that of normal RSA key-generation time, implying that no one can detect the backdoor by observing time imparity.

  5. [Surgical therapy for reconstruction of body shape and contour following massive weight reduction].

    Science.gov (United States)

    Constantinescu, Mihai A; Olariu, Radu; Shafighi, Maziar

    2013-02-01

    The consequences of massive weight loss through bariatric procedures as well as diet are overall positive. However, the sequelae of massive weight loss present themselves as soft tissue redundancies in the areas of the lower abdomen, upper thigh, upper arm and breast as well as face and neck. This condition presents significant mechanical, physical and social day-to-day limitations for the quality of life of these patients. Surgical techniques are indicated for the reconstruction of the body shape and therapy of the above named problems and the coexistent psychosocial component. These surgical techniques involve dermolipectomies in different body areas and can lead to significant improvement. In view of the worldwide increase of adipositas and the increasing need for bariatric surgery, a parallel increase in demand for such reconstructive post-bariatric interventions can be foreseen. Early and precise information is crucial for the patients before engaging in weight reduction, as is the coverage of the costs of the resulting secondary reconstructive body contouring interventions by the insurance companies.

  6. SEB teams up with RSA

    Index Scriptorium Estoniae

    2011-01-01

    Globaalne kindlustusgrupp RSA ja SEB Pank teatasid 19. aprillil, et alustavad koostööd varakindlustustoodete pakkumisel SEB klientidele Eestis, mis tähendab seda, et RSAst saab ainus varakindlustuse pakkuja pangas

  7. SEB teams up with RSA

    Index Scriptorium Estoniae

    2011-01-01

    Globaalne kindlustusgrupp RSA ja SEB Pank teatasid 19. aprillil, et alustavad koostööd varakindlustustoodete pakkumisel SEB klientidele Eestis, mis tähendab seda, et RSAst saab ainus varakindlustuse pakkuja pangas

  8. Painless, safe, and efficacious noninvasive skin tightening, body contouring, and cellulite reduction using multisource 3DEEP radiofrequency.

    Science.gov (United States)

    Harth, Yoram

    2015-03-01

    In the last decade, Radiofrequency (RF) energy has proven to be safe and highly efficacious for face and neck skin tightening, body contouring, and cellulite reduction. In contrast to first-generation Monopolar/Bipolar and "X -Polar" RF systems which use one RF generator connected to one or more skin electrodes, multisource radiofrequency devices use six independent RF generators allowing efficient dermal heating to 52-55°C, with no pain or risk of other side effects. In this review, the basic science and clinical results of body contouring and cellulite treatment using multisource radiofrequency system (Endymed PRO, Endymed, Cesarea, Israel) will be discussed and analyzed. © 2015 Wiley Periodicals, Inc.

  9. Mathematical Attacks on RSA Cryptosystem

    Directory of Open Access Journals (Sweden)

    Imad K. Salah

    2006-01-01

    Full Text Available In this paper some of the most common attacks against Rivest, Shamir, and Adleman (RSA cryptosystem are presented. We describe the integer factoring attacks, attacks on the underlying mathematical function, as well as attacks that exploit details in implementations of the algorithm. Algorithms for each type of attacks are developed and analyzed by their complexity, memory requirements and area of usage.

  10. EFFICIENT ASIC ARCHITECTURE OF RSA CRYPTOSYSTEM

    Directory of Open Access Journals (Sweden)

    Varun Nehru

    2014-05-01

    Full Text Available This paper presents a unified architecture design of the RSA cryptosystem i.e. RSA cryptoaccelerator along with key-pair generation. A structural design methodology for the same is proposed and implemented. The purpose is to design a complete cryptosystem efficiently with reduced hardware redundancy. Individual modular architectures of RSA, Miller-Rabin Test and Extended Binary GCD algorithm are presented and then they are integrated. Standard algorithm for RSA has been used. The RSA datapath has further been transformed into DPA resistant design. The simulation and implementation results using 180nm technology are shown and prove the validity of the architecture.

  11. RSA and its Correctness through Modular Arithmetic

    Science.gov (United States)

    Meelu, Punita; Malik, Sitender

    2010-11-01

    To ensure the security to the applications of business, the business sectors use Public Key Cryptographic Systems (PKCS). An RSA system generally belongs to the category of PKCS for both encryption and authentication. This paper describes an introduction to RSA through encryption and decryption schemes, mathematical background which includes theorems to combine modular equations and correctness of RSA. In short, this paper explains some of the maths concepts that RSA is based on, and then provides a complete proof that RSA works correctly. We can proof the correctness of RSA through combined process of encryption and decryption based on the Chinese Remainder Theorem (CRT) and Euler theorem. However, there is no mathematical proof that RSA is secure, everyone takes that on trust!.

  12. Combinations of resting RSA and RSA reactivity impact maladaptive mood repair and depression symptoms

    Science.gov (United States)

    Yaroslavsky, Ilya; Bylsma, Lauren M.; Rottenberg, Jonathan; Kovacs, Maria

    2013-01-01

    We examined whether the combined indices of respiratory sinus arrhythmia at rest (resting RSA) and in response to a sad film (RSA reactivity) predict effective and ineffective responses to reduce sadness (adaptive vs. maladaptive mood repair) in women with histories of juvenile-onset depression (n = 74) and no history of major mental disorders (n = 75). Structural equation models were used to estimate latent resting RSA, depression, and adaptive and maladaptive mood repair and to test the study hypotheses. Results indicated that combinations of resting RSA+RSA reactivity (RSA patterns) predicted maladaptive mood repair, which in turn, mediated the effects of RSA pattern on depression. Further, RSA patterns moderated the depressogenic effects of maladaptive mood repair. RSA patterns were unrelated to adaptive mood repair. Our findings suggest that mood repair is one mechanism through which physiological vulnerabilities adversely affect mental health. PMID:23827087

  13. Cryptanalysis of a Type of CRT-Based RSA Algorithms

    Institute of Scientific and Technical Information of China (English)

    Bao-Dong Qini; Ming Li; Fan-Yu Kong

    2008-01-01

    It is well known that the Chinese Remainder Theorem (CRT) can greatly improve the performances of RSA cryptosystem in both running times and memory requirements. However, if the implementation of CRT-based RSA is careless, an attacker can reveal some secret information by exploiting hardware fault cryptanalysis. In this paper, we present some fault attacks on a type of CRT-RSA algorithms namely BOS type schemes including the original BOS scheme proposed by Blomer, Otto, and Seifert at CCS 2003 and its modified scheme proposed by Liu et al. at DASC 2006. We first demonstrate that if some special signed messages such as m = 0, ±1 are dealt carelessly, they can be exploited by an adversary to completely break the security of both the BOS scheme and Liu et al.'s scheme. Then we present a new permanent fault attack on the BOS scheme with a success probability about 25%. Lastly, we propose a polynomial time attack on Liu et al.'s CRT-RSA algorithm, which combines physical fault injection and lattice reduction techniques when the public exponent is short.

  14. A Provably Secure Asynchronous Proactive RSA Scheme

    Institute of Scientific and Technical Information of China (English)

    ZHANG Rui-shan; LI Qiang; CHEN Ke-fei

    2005-01-01

    The drawback of the first asynchronous proactive RSA scheme presented by Zhou in 2001, is that the se curity definition and security proof do not follow the approach of provable security. This paper presented a provably secure asynchronous proactive RSA scheme, which includes three protocols: initial key distribution protocol,signature generation protocol and share refreshing protocol. Taken these protocols together, a complete provably secure proactive RSA scheme was obtained. And the efficiency of the scheme is approximate to that of the scheme of Zhou.

  15. Lattice Based Attack on Common Private Exponent RSA

    Directory of Open Access Journals (Sweden)

    Santosh Kumar Ravva

    2012-03-01

    Full Text Available Lattice reduction is a powerful concept for solving diverse problems involving point lattices. Lattice reduction has been successfully utilizing in Number Theory, Linear algebra and Cryptology. Not only the existence of lattice based cryptosystems of hard in nature, but also has vulnerabilities by lattice reduction techniques. In this paper, we show that Wieners small private exponent attack, when viewed as a heuristic lattice based attack, is extended to attack many instances of RSA when they have the same small private exponent.

  16. Tip-leakage flow loss reduction in a two-stage turbine using axisymmetric-casing contouring

    Directory of Open Access Journals (Sweden)

    Wei Zuojun

    2014-10-01

    Full Text Available In order to reduce the losses caused by tip-leakage flow, axisymmetric contouring is applied to the casing of a two-stage unshrouded high pressure turbine (HPT of aero-engine in this paper. This investigation focuses on the effects of contoured axisymmetric-casing on the blade tip-leakage flow. While the size of tip clearance remains the same as the original design, the rotor casing and the blade tip are obtained with the same contoured arc shape. Numerical calculation results show that a promotion of 0.14% to the overall efficiency is achieved. Detailed analysis indicates that it reduces the entropy generation rate caused by the complex vortex structure in the rotor tip region, especially in the tip-leakage vortex. The low velocity region in the leading edge (LE part of the tip gap is enlarged and the pressure side/tip junction separation bubble extends much further away from the leading edge in the clearance. So the blocking effect of pressure side/tip junction separation bubble on clearance flow prevents more flow on the tip pressure side from leaking to the suction side, which results in weaker leakage vortex and less associated losses.

  17. Improved Mask Protected DES using RSA Algorithm

    Directory of Open Access Journals (Sweden)

    Asha Latha S.

    2016-01-01

    Full Text Available The data encryption standard is a pioneering and farsighted standard which helped to set a new paradigm for encryption standards. But now DES is considered to be insecure for some application. Asymmetric mask protected DES is an advanced encryption method for effectively protecting the advanced DES. There are still probabilities to improve its security. This paper propose a method, which introduce a RSA key generation scheme in mask protected DES instead of plain key, which result in enhancement in the security of present asymmetric mask protected DES. We further propose a Vedic mathematical method of RSA implementation which reduce the complexity of computation in RSA block thereby resulting in reduced delay (four timesthat improves the performance of overall system. The software implementation was performed using Xilinx 13.2 and Model-Sim was used for the simulation environment.

  18. Revisiting Fermat's Factorization for the RSA Modulus

    CERN Document Server

    Gupta, Sounak

    2009-01-01

    We revisit Fermat's factorization method for a positive integer $n$ that is a product of two primes $p$ and $q$. Such an integer is used as the modulus for both encryption and decryption operations of an RSA cryptosystem. The security of RSA relies on the hardness of factoring this modulus. As a consequence of our analysis, two variants of Fermat's approach emerge. We also present a comparison between the two methods' effective regions. Though our study does not yield a new state-of-the-art algorithm for integer factorization, we believe that it reveals some interesting observations that are open for further analysis.

  19. Hardware modules of the RSA algorithm

    Directory of Open Access Journals (Sweden)

    Škobić Velibor

    2014-01-01

    Full Text Available This paper describes basic principles of data protection using the RSA algorithm, as well as algorithms for its calculation. The RSA algorithm is implemented on FPGA integrated circuit EP4CE115F29C7, family Cyclone IV, Altera. Four modules of Montgomery algorithm are designed using VHDL. Synthesis and simulation are done using Quartus II software and ModelSim. The modules are analyzed for different key lengths (16 to 1024 in terms of the number of logic elements, the maximum frequency and speed.

  20. Contouring and dose calculation in head and neck cancer radiotherapy after reduction of metal artifacts in CT images

    DEFF Research Database (Denmark)

    Hansen, Christian Rønn; Lübeck Christiansen, Rasmus; Lorenzen, Ebbe Laugaard

    2017-01-01

    Background: Delineation accuracy of the gross tumor volume (GTV) in radiotherapy planning for head and neck (H&N) cancer is affected by computed tomography (CT) artifacts from metal implants which obscure identification of tumor as well as organs at risk (OAR). This study investigates the impact...... region preceding curative radiotherapy (RT). The GTV-tumor (GTV-T), GTV-node and parotid glands were contoured by four independent observers on standard CT images and MAR images. Dose calculation was evaluated on thirty H&N patients with dental implants near the treated volume. For each patient, the dose...

  1. Data Security With Colors Using Rsa

    Directory of Open Access Journals (Sweden)

    G. Sankara Rao,

    2014-04-01

    Full Text Available Data Security with Colors using RSA technique that integrates the RGB Color model with the well-known public key cryptographic algorithm RSA (Rivest, Shamir and Adleman. This model provides both confidentiality and authentication to the data sent across the network. RSA algorithm uses public key and private key to encrypt and decrypt the data and thus provides confidentiality. But the public key is known to everyone and so anyone can encrypt the data and send the message. Hence authentication of users is needed. In this technique we use RGB color model to provide authentication. Every user will have a unique color assigned to him. A sender must know the receiver’s color to send a message. The color value is encrypted using a key which is used as a password while decrypting the message. To decrypt the message, the receiver must provide his color values. If the decrypted color values and his color values are equal then the sender and receiver are send to be authentic. The data encryption and decryption follows RSA procedure. Thus both authentication and confidentiality are provided for the data.

  2. Contour Tones.

    Science.gov (United States)

    Yip, Moira

    1989-01-01

    Argues that contour tones in East Asian languages behave as melodic units consisting of a root node [upper] dominating a branching specification. It is also argued that, with upper as the tonal root node, no more than two rising or falling tones will contrast underlying. (49 references) (JL)

  3. Remarks on the bounds for cryptanalysis of low private key RSA

    Institute of Scientific and Technical Information of China (English)

    Haijian Zhou; Ping Luo; Daoshun Wang; Yiqi Dai

    2009-01-01

    Boneh and Durfee have developed a cryptanalytic algorithm on low private key RSA. The algorithm is based on lattice basis reduc-tion and breaks RSA with private key d < N0.292. Later on, an improved version by Blomer and May enhanced the efficiency, while reaching approximately this same upper bound. Unfortunately, in both the algorithms, there is a critical error in theoretical analysis, leading to the overestimated upper bound N0.292. In this paper we present a more precise analytical model, with which the theoretical upper bound on d is modified to approximately d < N0.277 for ordinary RSA systems with a 1024-bit public key (N, e).

  4. RSA algoritam i njegova praktična primena / RSA algorithm

    Directory of Open Access Journals (Sweden)

    Sonja R. Kuljanski

    2010-07-01

    Full Text Available RSA algoritam jeste algoritam sa javnim ključem koji uključuje tri koraka: generisanje ključa, enkripciju i dekripciju. RSA enkripciona šema je determinističaka što znači da se osnovni tekst uvek enkriptuje u isti šifrovani tekst za unapred zadati javni ključ. Da bi se izbegao ovaj problem, praktična implementacija RSA algoritma obično koristi neke strukture, kao što je dodavanje slučajnog teksta u samu poruku pre enkripcije. Ovo dodavanje obezbeđuje da osnovna poruka bude sigurna i da se može enkriptovati u veliki broj različitih šifrovanih poruka. Standardi, kao što je PKCS #1, pažljivo su dizajnirani tako da dodaju tekst u osnovnu poruku pre RSA same enkripcije. / RSA is an algorithm for public-key encryption. It is the first algorithm known to be suitable for encryption as well as digital signing. The RSA encryption scheme is deterministic in the sense that under a fixed public key, a particular plaintext is always encrypted to the same ciphertext. A deterministic encryption scheme (as opposed to a probabilistic encryption scheme is a cryptosystem which always produces the same ciphertext for a given plaintext and key, even over separate executions of the encryption algorithm. Probabilistic encryption uses randomness in an encryption algorithm, so that when encrypting the same message several times it will, in general, yield different ciphertexts.

  5. Dynamic RSA: Examining parasympathetic regulatory dynamics via vector-autoregressive modeling of time-varying RSA and heart period.

    Science.gov (United States)

    Fisher, Aaron J; Reeves, Jonathan W; Chi, Cyrus

    2016-07-01

    Expanding on recently published methods, the current study presents an approach to estimating the dynamic, regulatory effect of the parasympathetic nervous system on heart period on a moment-to-moment basis. We estimated second-to-second variation in respiratory sinus arrhythmia (RSA) in order to estimate the contemporaneous and time-lagged relationships among RSA, interbeat interval (IBI), and respiration rate via vector autoregression. Moreover, we modeled these relationships at lags of 1 s to 10 s, in order to evaluate the optimal latency for estimating dynamic RSA effects. The IBI (t) on RSA (t-n) regression parameter was extracted from individual models as an operationalization of the regulatory effect of RSA on IBI-referred to as dynamic RSA (dRSA). Dynamic RSA positively correlated with standard averages of heart rate and negatively correlated with standard averages of RSA. We propose that dRSA reflects the active downregulation of heart period by the parasympathetic nervous system and thus represents a novel metric that provides incremental validity in the measurement of autonomic cardiac control-specifically, a method by which parasympathetic regulatory effects can be measured in process.

  6. Privacy Protection in Cloud Using Rsa Algorithm

    Directory of Open Access Journals (Sweden)

    Amandeep Kaur

    2014-05-01

    Full Text Available The cloud computing architecture has been on high demand nowadays. The cloud has been successful over grid and distributed environment due to its cost and high reliability along with high security. However in the area of research it is observed that cloud computing still has some issues in security regarding privacy. The cloud broker provide services of cloud to general public and ensures that data is protected however they sometimes lag security and privacy. Thus in this work of research an architecture is developed to preserve the security in two phases that is by RSA algorithm and auto-backup policy. Keywords:-

  7. Compensation for occupational diseases in the RSA.

    Science.gov (United States)

    Myers, J E; Garisch, D; Cornell, J E

    1987-03-01

    Compensation legislation for occupational disease in the RSA is at present complex and non-uniform, and the administrative bodies that process compensation claims are understaffed. In this setting occupational disease, particularly in migrant workers who are often ignorant of their rights under the law, frequently goes uncompensated. General practitioners and medical officers need to be aware of the basic provisions in the law, and how to submit claims in the best interests of their patients. Some case studies are included to illustrate problematic areas. The responsibilities of doctors in the diagnosis and compensation of occupational diseases are addressed.

  8. The multi-dimension RSA and its low exponent security

    Institute of Scientific and Technical Information of China (English)

    曹珍富

    2000-01-01

    Using a well-known result of polynomial over the finite field , we show that the Euler-Fermat theorem holds in N[ x]. We present a multi-dimension RSA cryptosystem and point out that low exponent algorithm of attacking RSA is not suitable for the multi-dimension RSA. Therefore, it is believed that the security of the new cryptosystem is mainly based on the factorization of large integers.

  9. An RSA-Based Leakage-Resilient Authenticated Key Exchange Protocol Secure against Replacement Attacks, and Its Extensions

    Science.gov (United States)

    Shin, Seonghan; Kobara, Kazukuni; Imai, Hideki

    Secure channels can be realized by an authenticated key exchange (AKE) protocol that generates authenticated session keys between the involving parties. In [32], Shin et al., proposed a new kind of AKE (RSA-AKE) protocol whose goal is to provide high efficiency and security against leakage of stored secrets as much as possible. Let us consider more powerful attacks where an adversary completely controls the communications and the stored secrets (the latter is denoted by “replacement” attacks). In this paper, we first show that the RSA-AKE protocol [32] is no longer secure against such an adversary. The main contributions of this paper are as follows: (1) we propose an RSA-based leakage-resilient AKE (RSA-AKE2) protocol that is secure against active attacks as well as replacement attacks; (2) we prove that the RSA-AKE2 protocol is secure against replacement attacks based on the number theory results; (3) we show that it is provably secure in the random oracle model, by showing the reduction to the RSA one-wayness, under an extended model that covers active attacks and replacement attacks; (4) in terms of efficiency, the RSA-AKE2 protocol is comparable to [32] in the sense that the client needs to compute only one modular multiplication with pre-computation; and (5) we also discuss about extensions of the RSA-AKE2 protocol for several security properties (i.e., synchronization of stored secrets, privacy of client and solution to server compromise-impersonation attacks).

  10. Anthropometric measurements of ankle mortise for evaluating mortise fracture reductions with an aim to develop contoured implants

    Directory of Open Access Journals (Sweden)

    M.S. Patil

    2012-10-01

    Full Text Available Background: Ankle injuries are unique as they are not only intra-articular of weight bearing joint, but also caused by a variety of mechanism, each resulting in different pattern with ankle fractures. The primary concern is residual instability of the joint as malalignment or residual displacement can adversely affect the biomechanical behaviour of ankle and resulting loss of function, due to non restoration of normal anatomy. Therefore essential of proper anatomical parameters for assessment of reduction and improved designs of implants used to get good results. Objectives: Measuring various radiological and Anatomical normal parameters of the ankle mortise. Material and Methods: Cadaveric 20 fibula and 27 tibia. Anteroposterior and 15○ internal rotation radiographs, of both Ankles in 20 adult individuals formed the material. Following parameters measured- a Tibiofibular clearspace b Tibiofibular overlap c Talocrural angle d Length of medial and lateral malleoli e Angles sustained on medial surface of medial malleoli and lateral surface of lateral malleoli. Results: a Tibiofibular clear space on Anteroposterior 2.4mm (±1.3mm in 15○ rotation 4.5mm (±1.2mm. b Tibiofibular overlap in Anteroposterior 11.2mm (±4.4mm in 15○ rotation 4.2mm (±1.7mm. c Talocrural angle in Anteroposterior 77.7mm (±3.2mm in 15○ rotation 79.9mm (±2.9mm. d Length of medial malleolus in Anteroposterior 15.3mm (±1.01mm in 15○ rotation 15.3mm (±0.8mm. e Length of lateral malleolus in Anteroposterior 27.35mm (±3.8mm in 15○ rotation 26.5mm (±5.1mm. Angles- Lateral bend of lateral malleolus was ranging 8○-21○ average being 16.2○. Medial bend of medial malleolus was ranging 10○-34○, average 19.5○. Conclusion: The unique measurement of angles on both surface of malleoli and other parameters definitely contribute for assessment of reduction and prognostic evaluations of ankle fracture, Designing, moulding and manufacturing of prebent plates for use

  11. Universally Composable Proactive Threshold RSA Signature

    Institute of Scientific and Technical Information of China (English)

    HONG Xuan; CHEN Ke-fei; LONG Yu

    2008-01-01

    Recently some efforts were made towards capturing the security requirements within the composable security framework.This modeling has some significant advantages in designing and analyzing complex systems.The threshold signature was discussed and a definition was given based on the universal composability framework,which is proved to be equivalent to the standard security definition.Furthermore,a simple,efficient and proactive threshold RSA signature protocol was presented.It is proved to be correct,consistent and unforgeable relative to the environment that at most t-1 parties are corrupted in each proactive stage.It is also secure under the universal composability framework.It is a UC based security and is proved to be equivalent to the standard security.

  12. Broadcast encryption schemes based on RSA

    Institute of Scientific and Technical Information of China (English)

    MU Ning-bo; HU Yu-pu; OU Hai-wen

    2009-01-01

    Three broadcast schemes for small receiver set using the property of RSA modulus are presented. They can solve the problem of data redundancy when the size of receiver set is small. In the proposed schemes, the center uses one key to encrypt the message and can revoke authorization conveniently. Every authorized user only needs to store one decryption key of a constant size. Among these three schemes, the first one has indistinguishability against adaptive chosen ciphertext attack (IND-CCA2) secure, and any collusion of authorized users cannot produce a new decryption key but the sizes of encryption modulus and ciphertext are linear in the number of receivers. In the second scheme, the size of ciphertext is half of the first one and any two authorized users can produce a new decryption key, but the center can identify them using the traitor tracing algorithm. The third one is the most efficient but the center cannot identify the traitors exactly.

  13. Simplifying Massive Contour Maps

    DEFF Research Database (Denmark)

    Arge, Lars; Deleuran, Lasse Kosetski; Mølhave, Thomas;

    2012-01-01

    We present a simple, efficient and practical algorithm for constructing and subsequently simplifying contour maps from massive high-resolution DEMs, under some practically realistic assumptions on the DEM and contours.......We present a simple, efficient and practical algorithm for constructing and subsequently simplifying contour maps from massive high-resolution DEMs, under some practically realistic assumptions on the DEM and contours....

  14. DETERMIN LARGE PRIME NUMBERS TO COMPUTE RSA SYSTEM PARAMETERS

    Directory of Open Access Journals (Sweden)

    Ioan Mang

    2008-05-01

    Full Text Available Cryptography, the secret writing, is probably same old as writing itself and has applications in data security insurance. There are cryptosystems where the encipher algorithm can be public. These are public key algorithms. Research on public key algorithms has been concerned with security aspects. The results of this research have induced sufficient confidence to apply public key cryptography a larger scale. The most used and checked public key-based cryptosystem was find by Rivest, Shamir and Adleman, so called RSA system. This paper shows the RSA algorithm. We have realised a program that is able to determine prime numbers with over 100 digits and compute RSA system parameters.

  15. On the Efficiency of Fast RSA Variants in Modern Mobile Phones

    CERN Document Server

    Hansen, Klaus; Olsen, Kim

    2010-01-01

    Modern mobile phones are increasingly being used for more services that require modern security mechanisms such as the public key cryptosystem RSA. It is, however, well known that public key cryptography demands considerable computing resources and that RSA encryption is much faster than RSA decryption. It is consequently an interesting question if RSA as a whole can be executed efficiently on modern mobile phones. In this paper, we explore the efficiency on modern mobile phones of variants of the RSA cryptosystem, covering CRT, MultiPrime RSA, MultiPower RSA, Rebalanced RSA and R Prime RSA by comparing the encryption and decryption time using a simple Java implementation and a typical RSA setup.

  16. Ocean Sediment Thickness Contours

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Ocean sediment thickness contours in 200 meter intervals for water depths ranging from 0 - 18,000 meters. These contours were derived from a global sediment...

  17. Tagged Vector Contour (TVC)

    Data.gov (United States)

    Kansas Data Access and Support Center — The Kansas Tagged Vector Contour (TVC) dataset consists of digitized contours from the 7.5 minute topographic quadrangle maps. Coverage for the state is incomplete....

  18. Fairfax County Contours

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — This layer contains contours that were derived from the digital terrain model made up of irregularly spaced mass points and breaklines. The contours are 5 foot...

  19. High Resolution Elevation Contours

    Data.gov (United States)

    Minnesota Department of Natural Resources — This dataset contains contours generated from high resolution data sources such as LiDAR. Generally speaking this data is 2 foot or less contour interval.

  20. Effect of advanced aircraft noise reduction technology on the 1990 projected noise environment around Patrick Henry Airport. [development of noise exposure forecast contours for projected traffic volume and aircraft types

    Science.gov (United States)

    Cawthorn, J. M.; Brown, C. G.

    1974-01-01

    A study has been conducted of the future noise environment of Patric Henry Airport and its neighboring communities projected for the year 1990. An assessment was made of the impact of advanced noise reduction technologies which are currently being considered. These advanced technologies include a two-segment landing approach procedure and aircraft hardware modifications or retrofits which would add sound absorbent material in the nacelles of the engines or which would replace the present two- and three-stage fans with a single-stage fan of larger diameter. Noise Exposure Forecast (NEF) contours were computed for the baseline (nonretrofitted) aircraft for the projected traffic volume and fleet mix for the year 1990. These NEF contours are presented along with contours for a variety of retrofit options. Comparisons of the baseline with the noise reduction options are given in terms of total land area exposed to 30 and 40 NEF levels. Results are also presented of the effects on noise exposure area of the total number of daily operations.

  1. RSA-Based Password-Authenticated Key Exchange, Revisited

    Science.gov (United States)

    Shin, Seonghan; Kobara, Kazukuni; Imai, Hideki

    The RSA-based Password-Authenticated Key Exchange (PAKE) protocols have been proposed to realize both mutual authentication and generation of secure session keys where a client is sharing his/her password only with a server and the latter should generate its RSA public/private key pair (e, n), (d, n) every time due to the lack of PKI (Public-Key Infrastructures). One of the ways to avoid a special kind of off-line (so called e-residue) attacks in the RSA-based PAKE protocols is to deploy a challenge/response method by which a client verifies the relative primality of e and φ(n) interactively with a server. However, this kind of RSA-based PAKE protocols did not give any proof of the underlying challenge/response method and therefore could not specify the exact complexity of their protocols since there exists another security parameter, needed in the challenge/response method. In this paper, we first present an RSA-based PAKE (RSA-PAKE) protocol that can deploy two different challenge/response methods (denoted by Challenge/Response Method1 and Challenge/Response Method2). The main contributions of this work include: (1) Based on the number theory, we prove that the Challenge/Response Method1 and the Challenge/Response Method2 are secure against e-residue attacks for any odd prime e (2) With the security parameter for the on-line attacks, we show that the RSA-PAKE protocol is provably secure in the random oracle model where all of the off-line attacks are not more efficient than on-line dictionary attacks; and (3) By considering the Hamming weight of e and its complexity in the. RSA-PAKE protocol, we search for primes to be recommended for a practical use. We also compare the RSA-PAKE protocol with the previous ones mainly in terms of computation and communication complexities.

  2. Deterministic and Probabilistic Approach in Primality Checking for RSA Algorithm

    Directory of Open Access Journals (Sweden)

    Sanjoy Das

    2013-04-01

    Full Text Available The RSA cryptosystem, invented by Ron Rivest, Adi Shamir and Len Adleman was first publicized in the August 1977 issue of Scientific American [1]. The security level of this algorithm very much depends on two large prime numbers [2]. In this paper two distinct approaches have been dealt with for primality checking. These are deterministic approach and probabilistic approach. For the deterministic approach, it has chosen modified trial division and for probabilistic approach, Miller-Rabin algorithm is considered. The different kinds of attacks on RSA and their remedy are also being discussed. This includes the chosen cipher text attacks, short private key exponent attack and frequency attack. Apart from these attacks, discussion has been made on how to choose the primes for the RSA algorithm. The time complexity has been demonstrated for the various algorithms implemented and compared with others. Finally the future modifications and expectations arising out of the current limitations have also been stated at the end.

  3. Security analysis of RSA cryptosystem algorithm and it's properties

    Science.gov (United States)

    Liu, Chenglian; Guo, Yongning; Lin, Juan

    2014-10-01

    The information technology rapidly development and dramatically changed the life style people, in addition to shortening the distance of communication, but also promote the smooth exchange of information flows. However, derivatives to facilitate the relative safety of these issues, since into the digital information age, the majority of the practitioners of engineering and technical personnel and technical workers in terms of technology, information security is increasingly becoming an important issue. The RSA algorithm was published in 1978. It is a kind of very popular and widely application modem cryptosystem in the world. Even though there are lots of articles to discuss about how to break the RSA, but it is still secure today. In this paper, the authors would like to introduce a variant attack to RSA.

  4. A New Factorization Method to Factorize RSA Public Key Encryption

    Directory of Open Access Journals (Sweden)

    Bhagvant Ram Ambedkar

    2011-11-01

    Full Text Available The security of public key encryption such as RSA scheme relied on the integer factoring problem. The security of RSA algorithm is based on positive integer N, because each transmitting node generates pair of keys such as public and private. Encryption and decryption of any message depends on N. Where, N is the product of two prime numbers and pair of key generation is dependent on these prime numbers. The factorization of N is very intricate. In this paper a New Factorization method is proposed to obtain the factor of positive integer N. The proposed work focuses on factorization of all trivial and nontrivial integer numbers and requires fewer steps for factorization process of RSA modulus N. The New Factorization method is based on Pollard rho factorization method. Experimental results shown that factorization speed is fast as compare existing methods.

  5. Batch Private Keys Generation for RSA in Security Communication Systems

    Institute of Scientific and Technical Information of China (English)

    CHEN Yun; CHEN Xin

    2005-01-01

    RSA public key cryptosystem is extensively used in information security systems.However, key generation for RSA cryptosystem requires multiplicative inversion over finite field, which has higher computational complexity, compared with either multiplication in common sense or modular multiplication over finite field. In order to improve the performance of key generation, we propose a batch private keys generation method in this paper. The method derives efficiency from cutting down multiplicative inversions over finite field. Theoretical analysis shows that the speed of batch private keys generation for s users is faster than that of s times solo private key generation. It is suitable for applications in those systems with large amount of users.

  6. MODEL KEAMANAN INFORMASI BERBASIS DIGITAL SIGNATURE DENGAN ALGORITMA RSA

    Directory of Open Access Journals (Sweden)

    Mohamad Ihwani

    2016-01-01

    Full Text Available Abstrak — Kerahasiaan dan keamanan data yang merupakan hal yang sangat penting, sehingga untuk menjaga kerahasiaan dan keamanan data perusahaan tersebut dapat dilakukan salah satunya dengan menggunakan teknik kriptografi. Digital Signature Algorithm (DSA merupakan salah satu kriptografi yang digunakan untuk nirpenyangkalan. DSA merupakan suatu tanda tangan elektronik yang dapat digunakan untuk membuktikan keaslian identitas pengirim atau penandatangan dari suatu pesan atau dokumen digital, namun DSA dengan fungsi hash tidak mengenkripsi plainteks asli sehingga, dikombinasikan dengan RSA.   Keywords :  Kriptografi, DSA, RSA.

  7. Efficient, Robust and Constant-Round Distributed RSA Key Generation

    DEFF Research Database (Denmark)

    Damgård, Ivan Bjerre; Mikkelsen, Gert Læssøe

    2010-01-01

    We present the first protocol for distributed RSA key generation which is constant round, secure against malicious adversaries and has a negligibly small bound on the error probability, even using only one iteration of the underlying primality test on each candidate number.......We present the first protocol for distributed RSA key generation which is constant round, secure against malicious adversaries and has a negligibly small bound on the error probability, even using only one iteration of the underlying primality test on each candidate number....

  8. The RSA Cryptoprocessor Hardware Implementation Based on Modified Montgomery Algorithm

    Institute of Scientific and Technical Information of China (English)

    CHEN Bo; WANG Xu; RONG Meng-tian

    2005-01-01

    RSA (Rivest-Shamir-Adleman)public-key cryptosystem is widely used in the information security area such as encryption and digital signature. Based on the modified Montgomery modular multiplication algorithm, a new architecture using CSA(carry save adder)was presented to implement modular multiplication. Compared with the popular modular multiplication algorithms using two CSA, the presented algorithm uses only one CSA, so it can improve the time efficiency of RSA cryptoprocessor and save about half of hardware resources for modular multiplication. With the increase of encryption data size n, the clock cycles for the encryption procedure reduce in T(n2) , compared with the modular multiplication algorithms using two CSA.

  9. Distributed Contour Trees

    Energy Technology Data Exchange (ETDEWEB)

    Morozov, Dmitriy; Weber, Gunther H.

    2014-03-31

    Topological techniques provide robust tools for data analysis. They are used, for example, for feature extraction, for data de-noising, and for comparison of data sets. This chapter concerns contour trees, a topological descriptor that records the connectivity of the isosurfaces of scalar functions. These trees are fundamental to analysis and visualization of physical phenomena modeled by real-valued measurements. We study the parallel analysis of contour trees. After describing a particular representation of a contour tree, called local{global representation, we illustrate how di erent problems that rely on contour trees can be solved in parallel with minimal communication.

  10. 对 Shor 算法破解 RSA 的探讨%Discussion on Cracking RSA With Shor Algorithm

    Institute of Scientific and Technical Information of China (English)

    凃玲英; 胡一凡; 张洪涛; 代永涛; 熊红梅

    2015-01-01

    Since the randomness of Shor algorithm could lead to low success rate in cracking RSA.By analyzing the prin-ciple of Shor algorithm,characteristics of RSA public key password system and lots of data,the view that the way for quantum functional in randomly selecting value is regular was putting forward .Verified by number theory and Monte Carlo method,the results showed that if takes a perfect square,the cycle probably can′t meet the requirements of Shor al-gorithm.It comes to a conclusion that take a non-perfect square can improve the success rate of Shor algorithm in cracking RSA.%针对 Shor 算法具有随机性,会导致破解 RSA 公钥密码体制成功率不高的问题,对 Shor 算法原理、RSA 公钥密码体制特点和大量计算结果进行分析,提出量子函数式 f (x)=ax mod n 对 a 值的随机选取是有规律的。结合数论知识和蒙特卡洛法证明,结果表明:随机数 a 取完全平方数,所求周期 r 很可能不满足 Shor算法要求;a 取非完全平方数可以提高 Shor 算法破解 RSA 的成功率。

  11. Use of the RSA/RCOD Index to Identify Training Priority in Soccer Players.

    Science.gov (United States)

    Wong, Del P; Hjelde, Geir H; Cheng, Ching-Feng; Ngo, Jake K

    2015-10-01

    The use of RSA/RCOD index indicates the repeated change-of-direction (RCOD) performance relative to the repeated-sprint ability (RSA) and provides a standardized approach to prioritize training needs for RSA and RCOD. To compare the RSA/RCOD index among different age groups, RSA and RCOD were measured from 20 under-16 players (U16), 20 under-19 players (U19), and 17 first-team professional players (PRO) from a football (soccer) club that has regular participation in the UEFA Champions League. Each player performed the RSA and RCOD tests, during which the fastest time (FT), average time (AT), total time (TT), and percentage decrement score (%Dec) were recorded. No significant differences were found in RSA/RCOD index-FT, AT, TT, and %Dec among the 3 groups (p > 0.05) and between U19 and PRO in all RSA and RCOD measures (p > 0.05). Most values of RSA/RCOD index were 0.51 among the U16, U19, and PRO groups. Moreover, we concluded that the RSA/RCOD index might not be further changed after 16 years of age unless specific training programs for RSA and RCOD are prescribed. Therefore, this study provides an empirical case, and coaches can establish the RSA/RCOD index value relevant to their training system and monitor players' training needs of RSA and RCOD in a longer term.

  12. The mathematics of ciphers number theory and RSA cryptography

    CERN Document Server

    Coutinho, S C

    1999-01-01

    This book is an introduction to the algorithmic aspects of number theory and its applications to cryptography, with special emphasis on the RSA cryptosys-tem. It covers many of the familiar topics of elementary number theory, all with an algorithmic twist. The text also includes many interesting historical notes.

  13. New generation of secure and practical RSA-based signatures

    NARCIS (Netherlands)

    R.J.F. Cramer (Ronald)

    1995-01-01

    textabstractFor most digital signature schemes used in practice, such as ISO9796/RSA or DSA, it has only been shown that certain plausible cryptographic assumptions, such as the difficulty of factoring integers, computing discrete logarithms or the collision-intractability of certain hash-functions

  14. RSA/Legacy Wind Sensor Comparison. Part 1; Western Range

    Science.gov (United States)

    Short, David A.; Wheeler, Mark M.

    2006-01-01

    This report describes a comparison of data from ultrasonic and cup-and-vane anemometers on 5 wind towers at Vandenberg AFB. The ultrasonic sensors are scheduled to replace the Legacy cup-and-vane sensors under the Range Standardization and Automation (RSA) program. Because previous studies have noted differences between peak wind speeds reported by mechanical and ultrasonic wind sensors, the latter having no moving parts, the 30th and 45th Weather Squadrons wanted to understand possible differences between the two sensor types. The period-of-record was 13-30 May 2005. A total of 153,961 readings of I-minute average and peak wind speed/direction from each sensor type were used. Statistics of differences in speed and direction were used to identify 18 out of 34 RSA sensors having the most consistent performance, with respect to the Legacy sensors. Data from these 18 were used to form a composite comparison. A small positive bias in the composite RSA average wind speed increased from +0.5 kts at 15 kts, to +1 kt at 25 kts. A slightly larger positive bias in the RSA peak wind speed increased from +1 kt at 15 kts, to +2 kts at 30 kts.

  15. RSA/Legacy Wind Sensor Comparison. Part 2; Eastern Range

    Science.gov (United States)

    Short, David A.; Wheeler, Mark M.

    2006-01-01

    This report describes a comparison of data from ultrasonic and propeller-and-vane anemometers on 5 wind towers at Kennedy Space Center and Cape Canaveral Air Force Station. The ultrasonic sensors are scheduled to replace the Legacy propeller-and-vane sensors under the Range Standardization and Automation (RSA) program. Because previous studies have noted differences between peak wind speeds reported by mechanical and ultrasonic wind sensors, the latter having no moving parts, the 30th and 45th Weather Squadrons wanted to understand possible differences between the two sensor types. The period-of-record was 13-30 May 2005, A total of 357,626 readings of 1-minute average and peak wind speed/direction from each sensor type were used. Statistics of differences in speed and direction were used to identify 15 out of 19 RSA sensors having the most consistent performance, with respect to the Legacy sensors. RSA average wind speed data from these 15 showed a small positive bias of 0.38 kts. A slightly larger positive bias of 0.94 kts was found in the RSA peak wind speed.

  16. Secure Batch Verification Protocol for RSA Signature Scheme

    Institute of Scientific and Technical Information of China (English)

    JIAZongpu; LIQingchao; LIZichen

    2005-01-01

    Harn, in 1998, proposed an efficient batch verification scheme for multiple RSA digital signatures.However, the scheme has a weakness, that is a signer can generate multiple signatures which can pass the batch verification scheme, but every one of these multiple signatures is not a valid signature. To avoid this disadvantage, we propose an improved batch verification scheme.

  17. On the Efficiency of Fast RSA Variants in Modern Mobile Phones

    DEFF Research Database (Denmark)

    Hansen, Klaus; Larsen, Troels; Olsen, Kim

    2009-01-01

    Modern mobile phones are increasingly being used for more services that require modern security mechanisms such as the public-key cryptosystem RSA. It is, however, well-known that public-key cryptography demands considerable computing resources and that RSA encryption is much faster than RSA...... decryption. It is consequently an interesting question if RSA as a whole can be executed efficiently on modern mobile phones....

  18. On the Efficiency of Fast RSA Variants in Modern Mobile Phones

    DEFF Research Database (Denmark)

    Hansen, Klaus; Larsen, Troels; Olsen, Kim

    2009-01-01

    Modern mobile phones are increasingly being used for more services that require modern security mechanisms such as the public-key cryptosystem RSA. It is, however, well-known that public-key cryptography demands considerable computing resources and that RSA encryption is much faster than RSA...... decryption. It is consequently an interesting question if RSA as a whole can be executed efficiently on modern mobile phones....

  19. Efficient and Robust Two-Party RSA Key Generation

    Institute of Scientific and Technical Information of China (English)

    YANG Muxiang; HONG Fan; ZHENG Minghui; LI Jun

    2006-01-01

    An efficient two party RSA secret key sharing generation scheme based on a homomorphic encryption, which is semantically secure under the prime residuosity assumption, is proposed in this paper. At the stage of computing RSA modulo N, an initial distributed primality test protocol is used to reduce the computation complexity and increase the probability of N being a two-prime product. On the other aspect, the homomorphic encryption based sharing conversion protocols is devised and adopted in multi-party computing modulus N and secret key d. Comparing to any sharing conversion protocols based on oblivious transfer protocol, the homomorphic encryption based sharing conversion protocols are of high performance. Our scheme resists the passive attack and since a method of verifying the sharing was introduced in, the scheme can resists any cheating behaviors too. Security proof, computation complexity and communication complexity analysis are given at last.

  20. APLIKASI KEAMANAN FILE AUDIO WAV (WAVEFORM DENGAN TERAPAN ALGORITMA RSA

    Directory of Open Access Journals (Sweden)

    Raja Nasrul Fuad

    2017-03-01

    Full Text Available The WAV file format that is widely used rough on various kinds of multimedia and gaming platforms. Ease of access and technological development with a variety of media to facilitate the exchange of information to various places. The data are important and need to be kept confidential secret for a wide range of security threats so that data can be intercepted and acknowledged by third parties during the shipping process. Of these problems led to the idea to create an application data security functions can secure the data using the RSA algorithm. The programming language is C # with Visual Studio software, the processed data is a sample each byte in WAV file, the header will be the same as that originally WAV files can be played even if the information has been withheld. RSA algorithm can be implemented into a programming language that WAV files can be processed and secured the data.

  1. Meteosat Images Encryption based on AES and RSA Algorithms

    Directory of Open Access Journals (Sweden)

    Boukhatem Mohammed Belkaid

    2015-06-01

    Full Text Available Satellite image Security is playing a vital role in the field of communication system and Internet. This work is interested in securing transmission of Meteosat images on the Internet, in public or local networks. To enhance the security of Meteosat transmission in network communication, a hybrid encryption algorithm based on Advanced Encryption Standard (AES and Rivest Shamir Adleman (RSA algorithms is proposed. AES algorithm is used for data transmission because of its higher efficiency in block encryption and RSA algorithm is used for the encryption of the key of the AES because of its management advantages in key cipher. Our encryption system generates a unique password every new session of encryption. Cryptanalysis and various experiments have been carried out and the results were reported in this paper, which demonstrate the feasibility and flexibility of the proposed scheme.

  2. A NEW RSA CRYPTOSYSTEM HARDWARE IMPLEMENTATION BASED ON MONTGOMERY'S ALGORITHM

    Institute of Scientific and Technical Information of China (English)

    卢君明; 林争辉

    2002-01-01

    RSA public key crypto-system is a relatively safe technology, which is widely used in today's secure electronic communication. In this paper, a new implementation method to optimize a 1 024 bit RSA processor was presented. Basically, a fast modular multiplication architecture based on Montgomery's algorithm was proposed. Modular exponentiation algorithm scans encryption from right to left, so two modular multiplications can be processed parallel. The new architecture is also fit for an effective I/O interface. The time to calculate a modular exponentiation is about n2 clock cycles. The proposed architecture has a data rate of 93.7 kb/s for 1 024 bit work with a 100 MHz clock.

  3. Adolescent RSA responses during an anger discussion task: Relations to emotion regulation and adjustment.

    Science.gov (United States)

    Cui, Lixian; Morris, Amanda Sheffield; Harrist, Amanda W; Larzelere, Robert E; Criss, Michael M; Houltberg, Benjamin J

    2015-06-01

    The current study examined associations between adolescent respiratory sinus arrhythmia (RSA) during an angry event discussion task and adolescents' emotion regulation and adjustment. Data were collected from 206 adolescents (10-18 years of age, M age = 13.37). Electrocardiogram (ECG) and respiration data were collected from adolescents, and RSA values and respiration rates were computed. Adolescents reported on their own emotion regulation, prosocial behavior, and aggressive behavior. Multilevel latent growth modeling was employed to capture RSA responses across time (i.e., linear and quadratic changes; time course approach), and adolescent emotion regulation and adjustment variables were included in the model to test their links to RSA responses. Results indicated that high RSA baseline was associated with more adolescent prosocial behavior. A pattern of initial RSA decreases (RSA suppression) in response to angry event recall and subsequent RSA increases (RSA rebound) were related to better anger and sadness regulation and more prosocial behavior. However, RSA was not significantly linked to adolescent aggressive behavior. We also compared the time course approach with the conventional linear approach and found that the time course approach provided more meaningful and rich information. The implications of adaptive RSA change patterns are discussed.

  4. Children's dynamic RSA change during anger and its relations with parenting, temperament, and control of aggression.

    Science.gov (United States)

    Miller, Jonas G; Chocol, Caroline; Nuselovici, Jacob N; Utendale, William T; Simard, Melissa; Hastings, Paul D

    2013-02-01

    This study examined the moderating effects of child temperament on the association between maternal socialization and 4-6-year-old children's dynamic respiratory sinus arrhythmia (RSA) change in response to anger-themed emotional materials (N=180). We used latent growth curve modeling to explore adaptive patterns of dynamic RSA change in response to anger. Greater change in RSA during anger-induction, characterized by more initial RSA suppression and a subsequent return to baseline, was related to children's better regulation of aggression. For anger-themed materials, low levels of authoritarian parenting predicted more RSA suppression and recovery for more anger-prone children, whereas more authoritative parenting predicted more RSA suppression and recovery for less anger-prone children. These findings suggest that children's adaptive patterns of dynamic RSA change can be characterized by latent growth curve modeling, and that these patterns may be differentially shaped by parent socialization experiences as a function of child temperament.

  5. Simplified Threshold RSA with Adaptive and Proactive Security

    DEFF Research Database (Denmark)

    Almansa Guerra, Jesus Fernando; Damgård, Ivan Bjerre; Nielsen, Jesper Buus

    2006-01-01

    We present the currently simplest, most efficient, optimally resilient, adaptively secure, and proactive threshold RSA scheme. A main technical contribution is a new rewinding strategy for analysing threshold signature schemes. This new rewinding strategy allows to prove adaptive security...... of a proactive threshold signature scheme which was previously assumed to be only statically secure. As a separate contribution we prove that our protocol is secure in the UC framework....

  6. An Efficient Proactive RSA Scheme for Ad Hoc Networks

    Institute of Scientific and Technical Information of China (English)

    ZHANG Rui-shan; CHEN Ke-fei

    2007-01-01

    A proactive threshold signature scheme is very important to tolerate mobile attack in mobile ad hoc networks. In this paper, we propose an efficient proactive threshold RSA signature scheme for ad hoc networks. The scheme consists of three protocols: the initial secret share distribution protocol, the signature generation protocol and the secret share refreshing protocol. Our scheme has three advantages. First, the signature generation protocol is efficient. Second, the signature generation protocol is resilient. Third, the share refreshing protocol is efficient.

  7. Reviews of computing technology: Securing network applications, Kerberos and RSA

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, S.M.

    1992-06-01

    This paper will focus on the first step in establishing network security, authentication, and describe the basic function of both RSA and Kerberos as used to provide authentication and confidential data transfer services. It will also discuss the Digital Signature Standard and the market acceptance of each. Proper identification of the principals involved in a network dialog is a necessary first step in providing network-wide security comparable to that of stand-alone systems.

  8. RSA Power Analysis Obfuscation: A Dynamic FPGA Architecture

    Science.gov (United States)

    2012-03-01

    research provides a VHDL coded dynamic architecture for synthesization on a Xilinx Virtex-5 FPGA. This architecture provides two-way communication...Component Under Test (CUT) is the dynamic RSA implementation. This dynamic hardware is synthesized from VHDL onto a Xilinx Virtex-5 FPGA. The built in...The hardware platform used for this research is a the Xil- inx Virtex-5 FX FPGA. VHDL code is synthesized using the Xilinx design suite and downloaded

  9. MODEL KEAMANAN INFORMASI BERBASIS DIGITAL SIGNATURE DENGAN ALGORITMA RSA

    Directory of Open Access Journals (Sweden)

    Mohamad Ihwani

    2016-01-01

    Full Text Available Kerahasiaan dan keamanan data yang merupakan hal yang sangat penting, sehingga untuk menjaga kerahasiaan dan keamanan data perusahaan tersebut dapat dilakukan salah satunya dengan menggunakan teknik kriptografi. Digital Signature Algorithm (DSA merupakan salah satu kriptografi yang digunakan untuk nirpenyangkalan. DSA merupakan suatu tanda tangan elektronik yang dapat digunakan untuk membuktikan keaslian identitas pengirim atau penandatangan dari suatu pesan atau dokumen digital, namun DSA dengan fungsi hash tidak mengenkripsi plainteks asli sehingga, dikombinasikan dengan RSA.

  10. Implementasi Algoritma Kriptografi RSA untuk Enkripsi dan Dekripsi Email

    Directory of Open Access Journals (Sweden)

    Albert Ginting

    2015-04-01

    Full Text Available In the world of Internet nothing is really safe. There's always a gap in any application made. Likewise in email delivery. To minimize attacks on the data transmission is usually applied cryptography. One fairly popular cryptographic algorithms are RSA algorithm. In this study will discuss the implementation of a cryptographic algorithm RSA encryption and decryption process email. To test created a java-based email client program with message encryption and decryption features messages. This application uses the Java programming language and Netbeans 7.4 as editor. Mail servers used is Google Mail. The initial step of this study was to download email from the Google server and encrypt the message. The second step is decrypt the message to verify whether the message is still the same as the original message before it is encrypted . Results from this study is the application that can encrypt and decrypt messages using RSA cryptographic algorithm. With this application is expected to mail delivery is much safer. Because encrypted email will generate a random decimal number of unknown value .

  11. Information-Theoretic Secure Verifiable Secret Sharing over RSA Modulus

    Institute of Scientific and Technical Information of China (English)

    QIU Gang; WANG Hong; WEI Shimin; XIAO Guozhen

    2006-01-01

    The well-known non-interactive and information-theoretic secure verifiable secret sharing scheme presented by Pedersen is over a large prime. In this paper, we construct a novel non-interactive and information-theoretic verifiable secret sharing over RSA (Rivest,Shamir,Adleman) modulus and give the rigorous security proof. It is shown how to distribute a secret among a group such that any set of k parties get no information about the secret. The presented scheme is generally applied to constructions of secure distributed multiplication and threshold or forward-secure signature protocols.

  12. RSA2009参展厂商速递

    Institute of Scientific and Technical Information of China (English)

    王伟

    2009-01-01

    2009年RSA Conference参展商数量减少到了大约325个,但还是引入了一些新的板块和议题吸引参与者,如IN-NOVATION SANDBOX、物理安全和其他安全相关的热点讨论,参与这次展览的厂商涉及到从Physical Security、IT Security 到Policy Compliance的方方面面.

  13. Efficient RSA Key Generation and Threshold Paillier in the Two-Party Setting

    DEFF Research Database (Denmark)

    Hazay, Carmit; Mikkelsen, Gert Læssøe; Rabin, Tal

    2011-01-01

    The problem of generating an RSA composite in a distributed manner without leaking its factorization is particularly challenging and useful in many cryptographic protocols. Our first contribution is the first non-generic fully simulatable protocol for distributively generating an RSA composite...... generation is comprised of the following: (i) a distributed protocol for generation of an RSA composite, and (ii) a biprimality test for verifying the validity of the generated composite. Our Paillier threshold encryption scheme uses the RSA composite as public key and is comprised of: (i) a distributed...... generation of the corresponding secret-key shares and, (ii) a distributed decryption protocol for decrypting according to Paillier....

  14. Visualization of Uncertain Contour Trees

    DEFF Research Database (Denmark)

    Kraus, Martin

    2010-01-01

    Contour trees can represent the topology of large volume data sets in a relatively compact, discrete data structure. However, the resulting trees often contain many thousands of nodes; thus, many graph drawing techniques fail to produce satisfactory results. Therefore, several visualization methods...... were proposed recently for the visualization of contour trees. Unfortunately, none of these techniques is able to handle uncertain contour trees although any uncertainty of the volume data inevitably results in partially uncertain contour trees. In this work, we visualize uncertain contour trees...... by combining the contour trees of two morphologically filtered versions of a volume data set, which represent the range of uncertainty. These two contour trees are combined and visualized within a single image such that a range of potential contour trees is represented by the resulting visualization. Thus...

  15. Efficient RSA Key Generation and Threshold Paillier in the Two-Party Setting

    DEFF Research Database (Denmark)

    Hazay, Carmit; Mikkelsen, Gert Læssøe; Rabin, Tal

    2012-01-01

    The problem of generating an RSA composite in a distributed manner without leaking its factorization is particularly challenging and useful in many cryptographic protocols. Our first contribution is the first non-generic fully simulatable protocol for distributively generating an RSA composite...

  16. ECC over RSA for Asymmetric Encryption-A Review

    Directory of Open Access Journals (Sweden)

    Kamlesh Gupta

    2011-05-01

    Full Text Available Cryptography is used to transmit the data securely in open network. This paper gives the survey of Elliptic Curve Cryptosystem (ECC used in many applications. ECC is a when compared to RSA and discrete logarithm systems, is a better option for the future. For this reason ECC is such an excellent choice for doing asymmetric cryptography in portable devices right now. The smaller ECC keys it turn makes the cryptographic operations that must be performed by the communicating devices to be embedded into considerably smaller hardware, so that software applications may complete cryptographic operations with fewer processor cycles, and operations can be performed much faster, while still retaining equivalent security. This means, in turn, reduced power consumption, less space consumed on the printed circuit board, and software applications that run more rapidly make lower memory demands. In brief, for communication using smaller devices and asymmetric cryptosystem we need ECC.

  17. Image Demosaicking with Contour Stencils

    Directory of Open Access Journals (Sweden)

    Pascal Getreuer

    2012-03-01

    Full Text Available Demosaicking (or demosaicing is the problem of interpolating full color information on an image where only one color component is known at each pixel. Most demosaicking methods involve some kind of estimation of the underlying image structure, for example, choosing adaptively between interpolating in the horizontal or vertical direction. This article discusses the implementation details of the method introduced in Getreuer, “Color Demosaicing with Contour Stencils,” 2011. Mosaicked contour stencils first estimate the image contour orientations directly from the mosaicked data. The mosaicked contour stencils are then used to guide a simple demosaicking method based on graph regularization.

  18. A randomized RSA study concentrating especially on continuous migration.

    Science.gov (United States)

    Molt, Mats; Ryd, Leif; Toksvig-Larsen, Sören

    2016-06-01

    Background and purpose - There is a general call for phased introduction of new implants, and one step in the introduction is an early evaluation of micromotion. We compared the micromotion in the Triathlon and its predecessor, the Duracon total knee prosthesis, concentrating especially on continuous migration over 5 years of follow-up. Patients and methods - 60 patients were randomized to receive either a cemented Triathlon total knee prosthesis or a cemented Duracon total knee prosthesis. 3-D tibial component migration was measured by radiostereometric analysis (RSA) at 3 months and at 1, 2, and 5 years. Results - There was no statistically significant difference in maximum total point motion (MTPM) between the 2 groups (p = 0.1). The mean MTPM at 5 years for the Duracon was 1.10 (SD 1.21) mm and for the Triathlon it was 0.66 (SD 0.38) mm. The numbers of continuously migrating prostheses were similar in the groups at the fifth year of follow-up; 6 of 21 prostheses in the Duracon group and 3 of 21 in the Triathlon group had migrated more than 0.3 mm between the second year and the fifth year of follow-up (p = 0.2). Interpretation - The Triathlon has a micromotion pattern similar to that of the Duracon total knee system at both short-term and medium-term follow-up, and may therefore, over time, show the same good long-term mechanical stability.

  19. Improved Trial Division Technique for Primality Checking in RSA Algorithm

    Directory of Open Access Journals (Sweden)

    Kumarjit Banerjee

    2012-07-01

    Full Text Available The RSA cryptosystem, invented by Ron Rivest, Adi Shamir and Len Adleman was first publicized in the August 1977 issue of Scientific American. The security level of this algorithm very much depends on two large prime numbers. To check the primality of large number in personal computer is huge time consuming using the best known trial division algorithm. The time complexity for primality testing has been reduced using the representation of divisors in the form of 6n±1. According to the fundamental theorem of Arithmetic, every number has unique factorization. So to check primality, it is sufficient to check if the number is divisible by any prime below the square root of the number. The set of divisors obtained by 6n±1 form representation contains many composites. These composite numbers have been reduced by 30k approach. In this paper, the number of composites has been further reduced using 210k approach. A performance analysis in time complexity has been given between 210k approach and other prior applied methods. It has been observed that the time complexity for primality testing has been reduced using 210k approach.

  20. VLSI implementation of RSA encryption system using ancient Indian Vedic mathematics

    Science.gov (United States)

    Thapliyal, Himanshu; Srinivas, M. B.

    2005-06-01

    This paper proposes the hardware implementation of RSA encryption/decryption algorithm using the algorithms of Ancient Indian Vedic Mathematics that have been modified to improve performance. The recently proposed hierarchical overlay multiplier architecture is used in the RSA circuitry for multiplication operation. The most significant aspect of the paper is the development of a division architecture based on Straight Division algorithm of Ancient Indian Vedic Mathematics and embedding it in RSA encryption/decryption circuitry for improved efficiency. The coding is done in Verilog HDL and the FPGA synthesis is done using Xilinx Spartan library. The results show that RSA circuitry implemented using Vedic division and multiplication is efficient in terms of area/speed compared to its implementation using conventional multiplication and division architectures.

  1. VLSI Implementation of RSA Encryption System Using Ancient Indian Vedic Mathematics

    OpenAIRE

    2006-01-01

    This paper proposes the hardware implementation of RSA encryption/decryption algorithm using the algorithms of Ancient Indian Vedic Mathematics that have been modified to improve performance. The recently proposed hierarchical overlay multiplier architecture is used in the RSA circuitry for multiplication operation. The most significant aspect of the paper is the development of a division architecture based on Straight Division algorithm of Ancient Indian Vedic Mathematics and embedding it in...

  2. Contours - MO 2012 Greene County 5ft Contours (SHP)

    Data.gov (United States)

    NSGIC State | GIS Inventory — 5ft cartographic contour file for Greene County, Missouri. This file was created using the elevation data from the 2011 LiDAR flight. It includes indexes for 10, 25,...

  3. Contours - MO 2012 Greene County 5ft Contours (SHP)

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — 5ft cartographic contour file for Greene County, Missouri. This file was created using the elevation data from the 2011 LiDAR flight. It includes indexes for 10, 25,...

  4. Contours - MO 2012 Greene County NW 1ft Contours (SHP)

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — 1ft contour file for the northwest portion of Greene County, Missouri. This file was created using the USGS corrected elevation data from the 2011 LiDAR flight. It...

  5. Contours - MO 2012 Greene County SE 1ft Contours (SHP)

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — 1ft contour file for the southeast portion of Greene County, Missouri. This file was created using the USGS corrected elevation data from the 2011 LiDAR flight. It...

  6. Contours - MO 2012 Greene County SW 1ft Contours (SHP)

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — 1ft contour file for the southwest portion of Greene County, Missouri. This file was created using the USGS corrected elevation data from the 2011 LiDAR flight. It...

  7. Contours - MO 2012 Greene County NE 1ft Contours (SHP)

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — 1ft contour file for the northeast portion of Greene County, Missouri. This file was created using the USGS corrected elevation data from the 2011 LiDAR flight. It...

  8. Wavelet Representation of Contour Sets

    Energy Technology Data Exchange (ETDEWEB)

    Bertram, M; Laney, D E; Duchaineau, M A; Hansen, C D; Hamann, B; Joy, K I

    2001-07-19

    We present a new wavelet compression and multiresolution modeling approach for sets of contours (level sets). In contrast to previous wavelet schemes, our algorithm creates a parametrization of a scalar field induced by its contoum and compactly stores this parametrization rather than function values sampled on a regular grid. Our representation is based on hierarchical polygon meshes with subdivision connectivity whose vertices are transformed into wavelet coefficients. From this sparse set of coefficients, every set of contours can be efficiently reconstructed at multiple levels of resolution. When applying lossy compression, introducing high quantization errors, our method preserves contour topology, in contrast to compression methods applied to the corresponding field function. We provide numerical results for scalar fields defined on planar domains. Our approach generalizes to volumetric domains, time-varying contours, and level sets of vector fields.

  9. Visualizing Contour Trees within Histograms

    DEFF Research Database (Denmark)

    Kraus, Martin

    2010-01-01

    Many of the topological features of the isosurfaces of a scalar volume field can be compactly represented by its contour tree. Unfortunately, the contour trees of most real-world volume data sets are too complex to be visualized by dot-and-line diagrams. Therefore, we propose a new visualization...... that is suitable for large contour trees and efficiently conveys the topological structure of the most important isosurface components. This visualization is integrated into a histogram of the volume data; thus, it offers strictly more information than a traditional histogram. We present algorithms...... to automatically compute the graph layout and to calculate appropriate approximations of the contour tree and the surface area of the relevant isosurface components. The benefits of this new visualization are demonstrated with the help of several publicly available volume data sets....

  10. Contours--Offshore Monterey, California

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This part of DS 781 presents bathymetric contours for several seafloor maps of the Monterey Canyon and Vicinity map area, California. The raster data file is...

  11. Contours--Offshore Aptos, California

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This part of DS 781 presents data for the bathymetric contours for several seafloor maps of the Offshore of Aptos map area, California. The vector data file is...

  12. Contours--Offshore Aptos, California

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This part of DS 781 presents data for the bathymetric contours for several seafloor maps of the Offshore of Aptos map area, California. The vector data file is...

  13. Contours--Offshore Monterey, California

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This part of DS 781 presents bathymetric contours for several seafloor maps of the Monterey Canyon and Vicinity map area, California. The raster data file is...

  14. Optimality of human contour integration.

    Directory of Open Access Journals (Sweden)

    Udo A Ernst

    Full Text Available For processing and segmenting visual scenes, the brain is required to combine a multitude of features and sensory channels. It is neither known if these complex tasks involve optimal integration of information, nor according to which objectives computations might be performed. Here, we investigate if optimal inference can explain contour integration in human subjects. We performed experiments where observers detected contours of curvilinearly aligned edge configurations embedded into randomly oriented distractors. The key feature of our framework is to use a generative process for creating the contours, for which it is possible to derive a class of ideal detection models. This allowed us to compare human detection for contours with different statistical properties to the corresponding ideal detection models for the same stimuli. We then subjected the detection models to realistic constraints and required them to reproduce human decisions for every stimulus as well as possible. By independently varying the four model parameters, we identify a single detection model which quantitatively captures all correlations of human decision behaviour for more than 2000 stimuli from 42 contour ensembles with greatly varying statistical properties. This model reveals specific interactions between edges closely matching independent findings from physiology and psychophysics. These interactions imply a statistics of contours for which edge stimuli are indeed optimally integrated by the visual system, with the objective of inferring the presence of contours in cluttered scenes. The recurrent algorithm of our model makes testable predictions about the temporal dynamics of neuronal populations engaged in contour integration, and it suggests a strong directionality of the underlying functional anatomy.

  15. Are CT Scans a Satisfactory Substitute for the Follow-Up of RSA Migration Studies of Uncemented Cups? A Comparison of RSA Double Examinations and CT Datasets of 46 Total Hip Arthroplasties

    Directory of Open Access Journals (Sweden)

    Volker Otten

    2017-01-01

    Full Text Available As part of the 14-year follow-up of a prospectively randomized radiostereometry (RSA study on uncemented cup fixation, two pairs of stereo radiographs and a CT scan of 46 hips were compared. Tantalum beads, inserted during the primary operation, were detected in the CT volume and the stereo radiographs and used to produce datasets of 3D coordinates. The limit of agreement between the combined CT and RSA datasets was calculated in the same way as the precision of the double RSA examination. The precision of RSA corresponding to the 99% confidence interval was 1.36°, 1.36°, and 0.60° for X-, Y-, and Z-rotation and 0.40, 0.17, and 0.37 mm for X-, Y-, and Z-translation. The limit of agreement between CT and RSA was 1.51°, 2.17°, and 1.05° for rotation and 0.59, 0.56, and 0.74 mm for translation. The differences between CT and RSA are close to the described normal 99% confidence interval for precision in RSA: 0.3° to 2° for rotation and 0.15 to 0.6 mm for translation. We conclude that measurements using CT and RSA are comparable and that CT can be used for migration studies for longitudinal evaluations of patients with RSA markers.

  16. Longitudinal associations between temperament and socioemotional outcomes in young children: the moderating role of RSA and gender.

    Science.gov (United States)

    Morales, Santiago; Beekman, Charles; Blandon, Alysia Y; Stifter, Cynthia A; Buss, Kristin A

    2015-01-01

    Temperament is an important predictor of socioemotional adjustment, such as externalizing and internalizing symptoms. However, there is not a one-to-one correspondence between temperamental predispositions and these outcomes, implying that other factors also contribute to the development of internalizing and externalizing problems. Self-regulation is believed to interact with temperament, and has been studied as a predictor for later socioemotional outcomes. Respiratory sinus arrhythmia (RSA) is a psychophysiological measure of self-regulation that has been studied as a moderator of risk. The primary aim of the present study was to test if RSA baseline and RSA reactivity would moderate the link between temperament and socioemotional outcomes. Mothers reported the temperament of their infants (20 months; N = 154), RSA was collected at 24- and 42-months, and mothers reported externalizing and internalizing behaviors at kindergarten entry. RSA baseline and RSA reactivity moderated the relation between exuberant temperament and externalizing behaviors. However, these results were only significant for girls, such that high RSA baseline and greater RSA suppression predicted more externalizing behaviors when exuberance was high. Fearful temperament predicted later internalizing behaviors, but no moderation was present. These results are discussed in light of recent evidence regarding gender differences in the role of RSA as a protective factor for risk.

  17. A Proposed Algorithm to improve security & Efficiency of SSL-TLS servers using Batch RSA decryption

    CERN Document Server

    Pateriya, R K; Shrivastava, S C; Patel, Jaideep

    2009-01-01

    Today, Internet becomes the essential part of our lives. Over 90 percent of the ecommerce is developed on the Internet. A security algorithm became very necessary for producer client transactions assurance and the financial applications safety. The rsa algorithm applicability derives from algorithm properties like confidentiality, safe authentication, data safety and integrity on the internet. Thus, this kind of networks can have a more easy utilization by practical accessing from short, medium, even long distance and from different public places. Rsa encryption in the client side is relatively cheap, whereas, the corresponding decryption in the server side is expensive because its private exponent is much larger. Thus ssl tls servers become swamped to perform public key decryption operations when the simultaneous requests increase quickly .The batch rsa method is useful for such highly loaded web server .In our proposed algorithm by reducing the response time and clients tolerable waiting time an improvement...

  18. Security analysis of RSA cryptosystem algorithm and it’s properties

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Chenglian [School of Mathematics and Computer Science, Long Yan university, Lonyan 364012 (China); Guo, Yongning, E-mail: guoyn@163.com, E-mail: linjuanliucaihong@qq.com; Lin, Juan, E-mail: guoyn@163.com, E-mail: linjuanliucaihong@qq.com [Department of Mathematics and Computer Science, Fuqing Branch of Fujian Normal University, Fuqing 350300 (China)

    2014-10-06

    The information technology rapidly development and dramatically changed the life style people, in addition to shortening the distance of communication, but also promote the smooth exchange of information flows. However, derivatives to facilitate the relative safety of these issues, since into the digital information age, the majority of the practitioners of engineering and technical personnel and technical workers in terms of technology, information security is increasingly becoming an important issue. The RSA algorithm was published in 1978. It is a kind of very popular and widely application modem cryptosystem in the world. Even though there are lots of articles to discuss about how to break the RSA, but it is still secure today. In this paper, the authors would like to introduce a variant attack to RSA.

  19. Topological Cacti: Visualizing Contour-based Statistics

    Energy Technology Data Exchange (ETDEWEB)

    Weber, Gunther H.; Bremer, Peer-Timo; Pascucci, Valerio

    2011-05-26

    Contours, the connected components of level sets, play an important role in understanding the global structure of a scalar field. In particular their nestingbehavior and topology-often represented in form of a contour tree-have been used extensively for visualization and analysis. However, traditional contour trees onlyencode structural properties like number of contours or the nesting of contours, but little quantitative information such as volume or other statistics. Here we use thesegmentation implied by a contour tree to compute a large number of per-contour (interval) based statistics of both the function defining the contour tree as well asother co-located functions. We introduce a new visual metaphor for contour trees, called topological cacti, that extends the traditional toporrery display of acontour tree to display additional quantitative information as width of the cactus trunk and length of its spikes. We apply the new technique to scalar fields ofvarying dimension and different measures to demonstrate the effectiveness of the approach.

  20. Illusory contour formation survives crowding.

    Science.gov (United States)

    Lau, Jonathan Siu Fung; Cheung, Sing-Hang

    2012-06-12

    Flanked objects are difficult to identify using peripheral vision due to visual crowding, which limits conscious access to target identity. Nonetheless, certain types of visual information have been shown to survive crowding. Such resilience to crowding provides valuable information about the underlying neural mechanism of crowding. Here we ask whether illusory contour formation survives crowding of the inducers. We manipulated the presence of illusory contours through the (mis)alignment of the four inducers of a Kanizsa square. In the inducer-aligned condition, the observers judged the perceived shape (thin vs. fat) of the illusory Kanizsa square, manipulated by small rotations of the inducers. In the inducer-misaligned condition, three of the four inducers (all except the upper-left) were rotated 90°. The observers judged the orientation of the upper-left inducer. Crowding of the inducers worsened observers' performance significantly only in the inducer-misaligned condition. Our findings suggest that information for illusory contour formation survives crowding of the inducers. Crowding happens at a stage where the low-level featural information is integrated for inducer orientation discrimination, but not at a stage where the same information is used for illusory contour formation.

  1. Towards Stabilizing Parametric Active Contours

    DEFF Research Database (Denmark)

    Liu, Jinchao; Fan, Zhun; Olsen, Søren Ingvor;

    2014-01-01

    Numerical instability often occurs in evolving of parametric active contours. This is mainly due to the undesired change of parametrization during evolution. In this paper, we propose a new tangential diffusion term to compensate this undesired change. As a result, the parametrization will converge...

  2. Contour Detection by CORF Operator

    NARCIS (Netherlands)

    Azzopardi, George; Petkov, Nicolai

    2012-01-01

    We propose a contour operator, called CORF, inspired by the properties of simple cells in visual cortex. It combines, by a weighted geometric mean, the blurred responses of difference-of-Gaussian operators that model cells in the lateral geniculate nucleus (LGN). An operator that has gained

  3. High-precision measurements of cementless acetabular components using model-based RSA: an experimental study

    DEFF Research Database (Denmark)

    Baad-Hansen, Thomas; Kold, Søren; Kaptein, Bart L;

    2007-01-01

    BACKGROUND: In RSA, tantalum markers attached to metal-backed acetabular cups are often difficult to detect on stereo radiographs due to the high density of the metal shell. This results in occlusion of the prosthesis markers and may lead to inconclusive migration results. Within the last few yea...

  4. Model-based shape matching of orthopaedic implants in RSA and fluoroscopy

    NARCIS (Netherlands)

    Prins, Anne Hendrik

    2015-01-01

    Model-based shape matching is commonly used, for example to measure the migration of an implant with Roentgen stereophotogrammetric analysis (RSA) or to measure implant kinematics with fluoroscopy. The aim of this thesis was to investigate the general usability of shape matching and to improve the r

  5. A collection of insurance brands: The story of RSA in Ireland

    Directory of Open Access Journals (Sweden)

    Richard Brophy

    2015-12-01

    Full Text Available Many firms in financial services opt for corporate branding in order to unify their activities and leverage a strong brand across business units. While this may be the case, some financial service organisations retain the approach of using a collection of brands within the organisation. RSA has opted to retain its existing brands while gaining market share in Ireland. This paper studies the approach that RSA has taken in its brand architecture. Through a literature review of branding and rebranding, along with a historical study of the RSA Company going back to its foundation, the author attempts to chart the direction of the company alongside industry changes, such as product distribution and also the introduction of other stakeholders to the marketplace. Unlike its insurance peers, RSA is one of the few insurers that operates a portfolio of brands that operate in different markets within the industry. While the company is well known as a large insurer in Ireland, it retains its existing brands in a successful way through its product distribution

  6. 50 CFR 648.207 - Herring Research Set-Aside (RSA).

    Science.gov (United States)

    2010-10-01

    ... 50 Wildlife and Fisheries 8 2010-10-01 2010-10-01 false Herring Research Set-Aside (RSA). 648.207... during the interim years and decides to publish a second RFP. Proposals to fund research that would start..., researchers must provide the Council and NMFS with a report of research findings, which must include:...

  7. HYBRID CHRIPTOGRAPHY STREAM CIPHER AND RSA ALGORITHM WITH DIGITAL SIGNATURE AS A KEY

    Directory of Open Access Journals (Sweden)

    Grace Lamudur Arta Sihombing

    2017-03-01

    Full Text Available Confidentiality of data is very important in communication. Many cyber crimes that exploit security holes for entry and manipulation. To ensure the security and confidentiality of the data, required a certain technique to encrypt data or information called cryptography. It is one of the components that can not be ignored in building security. And this research aimed to analyze the hybrid cryptography with symmetric key by using a stream cipher algorithm and asymmetric key by using RSA (Rivest Shamir Adleman algorithm. The advantages of hybrid cryptography is the speed in processing data using a symmetric algorithm and easy transfer of key using asymmetric algorithm. This can increase the speed of transaction processing data. Stream Cipher Algorithm using the image digital signature as a keys, that will be secured by the RSA algorithm. So, the key for encryption and decryption are different. Blum Blum Shub methods used to generate keys for the value p, q on the RSA algorithm. It will be very difficult for a cryptanalyst to break the key. Analysis of hybrid cryptography stream cipher and RSA algorithms with digital signatures as a key, indicates that the size of the encrypted file is equal to the size of the plaintext, not to be larger or smaller so that the time required for encryption and decryption process is relatively fast.

  8. Emotion suppression moderates the quadratic association between RSA and executive function.

    Science.gov (United States)

    Spangler, Derek P; Bell, Martha Ann; Deater-Deckard, Kirby

    2015-09-01

    There is uncertainty about whether respiratory sinus arrhythmia (RSA), a cardiac marker of adaptive emotion regulation, is involved in relatively low or high executive function performance. In the present study, we investigated (a) whether RSA during rest and tasks predict both relatively low and high executive function within a larger quadratic association among the two variables, and (b) the extent to which this quadratic trend was moderated by individual differences in emotion regulation. To achieve these aims, a sample of ethnically and socioeconomically diverse women self-reported reappraisal and emotion suppression. They next experienced a 2-min resting period during which electrocardiogram (ECG) was continually assessed. In the next phase, the women completed an array of executive function and nonexecutive cognitive tasks while ECG was measured throughout. As anticipated, resting RSA showed a quadratic association with executive function that was strongest for high suppression. These results suggest that relatively high resting RSA may predict poor executive function ability when emotion regulation consumes executive control resources needed for ongoing cognitive performance. © 2015 Society for Psychophysiological Research.

  9. Extending Algorithm of RSA Algorithm%基于RSA算法的扩展算法

    Institute of Scientific and Technical Information of China (English)

    张延招

    2011-01-01

    The security of RSA is designed on the basis of the difficulty of large integer decomposition.In the RSA public key encryption system the public key n is the product of two large prime number,aiming at the large integer n decomposition of the form n=pq(in which p,q as large prime number).The paper describes the encryption and decryption theory of extending RSA algorithm,aiming at the large integer n decomposition to the form n=p1,p2,…,pr(in which p1,p2,…,pr as large prime number).The addition of prime number could enhance the security of RSA algorithm.Compared to RSA algorithm,the extending RSA algorithm could be applied to both digital encryption/decryption and digital signature.Digital signature algorithm based on extending RSA algorithm is also of high security and reliability.%RSA的安全性是依据大整数分解的困难性而设计的。RSA公开密钥加密体制中n为2个大素数的乘积,即针对n=pq(p,q为大素数)的大整数分解,这里介绍了RSA算法的扩展算法的加密和解密原理,即针对n=p1,p2,…,pr(p1,p2,…,pr为大素数)的大整数分解。通过扩展素因子的个数达到RSA算法的安全性。比较RSA算法,扩展的RSA算法不仅可用于数据加密解密,也可用于数字签名。利用扩展的RSA算法实现数字签名也具有较高的安全性和可靠性。

  10. Wound Image Analysis Using Contour Evolution

    Directory of Open Access Journals (Sweden)

    K. Sundeep Kumar

    2014-05-01

    Full Text Available The aim of the algorithm described in this paper is to segment wound images from the normal and classify them according to the types of the wound. The segmentation of wounds extravagates color representation, which has been followed by an algorithm of grayscale segmentation based on the stack mathematical approach. Accurate classification of wounds and analyzing wound healing process is a critical task for patient care and health cost reduction at hospital. The tissue uniformity and flatness leads to a simplified approach but requires multispectral imaging for enhanced wound delineation. Contour Evolution method which uses multispectral imaging replaces more complex tools such as, SVM supervised classification, as no training step is required. In Contour Evolution, classification can be done by clustering color information, with differential quantization algorithm, the color centroids of small squares taken from segmented part of the wound image in (C1,C2 plane. Where C1, C2 are two chrominance components. Wound healing is identified by measuring the size of the wound through various means like contact and noncontact methods of wound. The wound tissues proportion is also estimated by a qualitative visual assessment based on the red-yellow-black code. Moreover, involving all the spectral response of the tissue and not only RGB components provides a higher discrimination for separating healed epithelial tissue from granulation tissue.

  11. Gulf of Mexico Deepwater Bathymetry Contours

    Data.gov (United States)

    Bureau of Ocean Energy Management, Department of the Interior — Gulf of Mexico Depth Contours derived from NOAA's NGDC bathymetric grids and from BOEM's seismic grid compilation. Both NOAA and BOEM contours are shown in meters or...

  12. From Inpainting to Active Contours

    DEFF Research Database (Denmark)

    Lauze, Francois Bernard; Nielsen, Mads

    2008-01-01

    image and a guess on the location of the object to be segmented via variational inpainting method. A numerical evaluation of this reconstruction provides a "disocclusion measure" and the correct foreground segmentation region is expected to maximize this measure. This formulation is in fact an optimal...... control problem, where controls are shapes/regions and states are the corresponding inpaintings. Optimization of the disocclusion measure leads formally to a coupled contour evolution equation, an inpainting equation (the state equation) as well as a linear PDE depending on the inpainting (the adjoint...... state equation). The contour evolution is implemented in the framework of level sets. Finally, the proposed method is validated on various examples. We focus among others in the segmentation of calcified plaques observed in radiographs from human lumbar aortic regions. Keywords  Segmentation - Inpainting...

  13. Applying manifold learning to plotting approximate contour trees.

    Science.gov (United States)

    Takahashi, Shigeo; Fujishiro, Issei; Okada, Masato

    2009-01-01

    A contour tree is a powerful tool for delineating the topological evolution of isosurfaces of a single-valued function, and thus has been frequently used as a means of extracting features from volumes and their time-varying behaviors. Several sophisticated algorithms have been proposed for constructing contour trees while they often complicate the software implementation especially for higher-dimensional cases such as time-varying volumes. This paper presents a simple yet effective approach to plotting in 3D space, approximate contour trees from a set of scattered samples embedded in the high-dimensional space. Our main idea is to take advantage of manifold learning so that we can elongate the distribution of high-dimensional data samples to embed it into a low-dimensional space while respecting its local proximity of sample points. The contribution of this paper lies in the introduction of new distance metrics to manifold learning, which allows us to reformulate existing algorithms as a variant of currently available dimensionality reduction scheme. Efficient reduction of data sizes together with segmentation capability is also developed to equip our approach with a coarse-to-fine analysis even for large-scale datasets. Examples are provided to demonstrate that our proposed scheme can successfully traverse the features of volumes and their temporal behaviors through the constructed contour trees.

  14. Grouping by proximity in haptic contour detection.

    Directory of Open Access Journals (Sweden)

    Krista E Overvliet

    Full Text Available We investigated the applicability of the Gestalt principle of perceptual grouping by proximity in the haptic modality. To do so, we investigated the influence of element proximity on haptic contour detection. In the course of four sessions ten participants performed a haptic contour detection task in which they freely explored a haptic random dot display that contained a contour in 50% of the trials. A contour was defined by a higher density of elements (raised dots, relative to the background surface. Proximity of the contour elements as well as the average proximity of background elements was systematically varied. We hypothesized that if proximity of contour elements influences haptic contour detection, detection will be more likely when contour elements are in closer proximity. This should be irrespective of the ratio with the proximity of the background elements. Results showed indeed that the closer the contour elements were, the higher the detection rates. Moreover, this was the case independent of the contour/background ratio. We conclude that the Gestalt law of proximity applies to haptic contour detection.

  15. Active Contour with A Tangential Component

    CERN Document Server

    Wang, Junyan

    2012-01-01

    Conventional edge-based active contours often require the normal component of an edge indicator function on the optimal contours to approximate zero, while the tangential component can still be significant. In real images, the full gradients of the edge indicator function along the object boundaries are often small. Hence, the curve evolution of edge-based active contours can terminate early before converging to the object boundaries with a careless contour initialization. We propose a novel Geodesic Snakes (GeoSnakes) active contour that requires the full gradients of the edge indicator to vanish at the optimal solution. Besides, the conventional curve evolution approach for minimizing active contour energy cannot fully solve the Euler-Lagrange (EL) equation of our GeoSnakes active contour, causing a Pseudo Stationary Phenomenon (PSP). To address the PSP problem, we propose an auxiliary curve evolution equation, named the equilibrium flow (EF) equation. Based on the EF and the conventional curve evolution, w...

  16. Algoritmo de criptografia RSA: análise entre a segurança e velocidade

    Directory of Open Access Journals (Sweden)

    Rafael Santos Andrade

    2012-12-01

    Full Text Available O objetivo deste trabalho é abordar a relação existente entre a busca pela segurança de dados e a velocidade de codificação e decodificação do algoritmo de criptografia RSA, que utiliza um par de números inteiros como ‘chave’. Considerando o tamanho da chave como requisito de segurança, devido à dificuldade computacional de fatorar números inteiros extensos, simulamos estes processos, com o algoritmo implementado na linguagem de programação C, utilizando chaves aleatórias de 1024, 2048 e 4096 bits. Desta forma, observamos o tempo de processamento em função do tamanho das chaves, confrontando segurança e desempenho.Palavras-chave: criptografia; algoritmo RSA; segurança; desempenho.

  17. Distributed Factorization Computation on Multiple Volunteered Mobile Resource to Break RSA Key

    Science.gov (United States)

    Jaya, I.; Hardi, S. M.; Tarigan, J. T.; Zamzami, E. M.; Sihombing, P.

    2017-01-01

    Similar to common asymmeric encryption, RSA can be cracked by usmg a series mathematical calculation. The private key used to decrypt the massage can be computed using the public key. However, finding the private key may require a massive amount of calculation. In this paper, we propose a method to perform a distributed computing to calculate RSA’s private key. The proposed method uses multiple volunteered mobile devices to contribute during the calculation process. Our objective is to demonstrate how the use of volunteered computing on mobile devices may be a feasible option to reduce the time required to break a weak RSA encryption and observe the behavior and running time of the application on mobile devices.

  18. RSA calibration accuracy of a fluoroscopy-based system using nonorthogonal images for measuring functional kinematics

    Energy Technology Data Exchange (ETDEWEB)

    Kedgley, Angela E.; Jenkyn, Thomas R. [Department of Mechanical and Materials Engineering, Faculty of Engineering, University of Western Ontario, London, Ontario N6A 5B9 (Canada); Wolf Orthopaedic Biomechanics Laboratory, Fowler Kennedy Sport Medicine Clinic, London, Ontario N6A 5B9 (Canada); Department of Mechanical and Materials Engineering, Faculty of Engineering, University of Western Ontario, London, Ontario N6A 5B9 (Canada) and School of Kinesiology, Faculty of Health Sciences, University of Western Ontario, London, Ontario N6A 5B9 (Canada)

    2009-07-15

    When performing radiostereometric analysis (RSA) in a clinical setting it may be desirable to orient the two imaging devices nonorthogonally to obtain the best views of an anatomical structure. In this study, a calibration frame was constructed that allowed the relative angles of fiducial and control planes to be adjusted. Precision and accuracy were quantified across multiple trials and orientations. The 90 deg. frame was always of equivalent or greater accuracy than a calibration frame with the fiducial and control planes aligned parallel to the image intensifiers. This study also showed that RSA may be performed with imaging devices at relative angles other than 90 deg. without compromising accuracy. This allows researchers greater freedom in positioning equipment.

  19. Precision measurements of the RSA method using a phantom model of hip prosthesis.

    Science.gov (United States)

    Mäkinen, Tatu J; Koort, Jyri K; Mattila, Kimmo T; Aro, Hannu T

    2004-04-01

    Radiostereometric analysis (RSA) has become one of the recommended techniques for pre-market evaluation of new joint implant designs. In this study we evaluated the effect of repositioning of X-ray tubes and phantom model on the precision of the RSA method. In precision measurements, we utilized mean error of rigid body fitting (ME) values as an internal control for examinations. ME value characterizes relative motion among the markers within each rigid body and is conventionally used to detect loosening of a bone marker. Three experiments, each consisting of 10 double examinations, were performed. In the first experiment, the X-ray tubes and the phantom model were not repositioned between one double examination. In experiments two and three, the X-ray tubes were repositioned between one double examination. In addition, the position of the phantom model was changed in experiment three. Results showed that significant differences could be found in 2 of 12 comparisons when evaluating the translation and rotation of the prosthetic components. Repositioning procedures increased ME values mimicking deformation of rigid body segments. Thus, ME value seemed to be a more sensitive parameter than migration values in this study design. These results confirmed the importance of standardized radiographic technique and accurate patient positioning for RSA measurements. Standardization and calibration procedures should be performed with phantom models in order to avoid unnecessary radiation dose of the patients. The present model gives the means to establish and to follow the intra-laboratory precision of the RSA method. The model is easily applicable in any research unit and allows the comparison of the precision values in different laboratories of multi-center trials.

  20. Hybrid information privacy system: integration of chaotic neural network and RSA coding

    Science.gov (United States)

    Hsu, Ming-Kai; Willey, Jeff; Lee, Ting N.; Szu, Harold H.

    2005-03-01

    Electronic mails are adopted worldwide; most are easily hacked by hackers. In this paper, we purposed a free, fast and convenient hybrid privacy system to protect email communication. The privacy system is implemented by combining private security RSA algorithm with specific chaos neural network encryption process. The receiver can decrypt received email as long as it can reproduce the specified chaos neural network series, so called spatial-temporal keys. The chaotic typing and initial seed value of chaos neural network series, encrypted by the RSA algorithm, can reproduce spatial-temporal keys. The encrypted chaotic typing and initial seed value are hidden in watermark mixed nonlinearly with message media, wrapped with convolution error correction codes for wireless 3rd generation cellular phones. The message media can be an arbitrary image. The pattern noise has to be considered during transmission and it could affect/change the spatial-temporal keys. Since any change/modification on chaotic typing or initial seed value of chaos neural network series is not acceptable, the RSA codec system must be robust and fault-tolerant via wireless channel. The robust and fault-tolerant properties of chaos neural networks (CNN) were proved by a field theory of Associative Memory by Szu in 1997. The 1-D chaos generating nodes from the logistic map having arbitrarily negative slope a = p/q generating the N-shaped sigmoid was given first by Szu in 1992. In this paper, we simulated the robust and fault-tolerance properties of CNN under additive noise and pattern noise. We also implement a private version of RSA coding and chaos encryption process on messages.

  1. Observation of switching between SA and RSA in silver/goldpolyaniline nanocomposite films

    Science.gov (United States)

    Anand, P. B.; Jayalekshmi, S.

    2013-09-01

    In the present work, attempts have been made to embed Silver (Ag) /Gold (Au) - nanoparticles into polyaniline (PANI) matrix using an easy wet chemical route. It is expected that the resulting nanocomposite will show the interesting third order nonlinear optical characteristics of Ag/Au-nanoparicles modified by the advantageous properties of the conducting polymer PANI. Structural characterisation of Ag/Au-PANI nanocomposite samples was done using X-ray diffraction and Raman studies. UV-visible absorption spectra show the presence of surface plasmon resonance (SPR) peaks centred at 410 nm and 520 nm for Ag-PANI and Au-PANI nanocomposite films respectively, which is a signature of nano dimensionality of the composite samples. Third order nonlinear behaviour of the nanocomposite films was analysed using Z Scan technique employing the second harmonic output (532 nm) of a Q-switched Nd:YAG laser (Minilite, Continuum). It is seen that Ag/Au-PANI nanocomposite film samples show simultaneous presence of saturable absorption (SA) and reversible saturable absorptions (RSA) behaviour at 50 μJ laser excitation. This switching between SA and RSA has been reported in many metal nanocomposite systems. However similar behavior in nanocomposite film samples has not been pursued much. The highlight of the present work is the observation of the switching between SA and RSA in Ag/Au polyaniline nanocomposite films. The switching behavior can be ascribed to the interplay between ground state plasmon band bleaching and excited state absorption. Two photon assisted absorption has been identified as the prime factor contributing towards the observed RSA in these nanocomposite films.

  2. 'n Ondersoek na die amalgamering van skole in die RSA / André Johann Nel

    OpenAIRE

    Nel, André Johann

    1999-01-01

    Rationalisation, because of a lack of governmental funds, has become part of the education system of the RSA. In schools it implies that teaching posts are being reduced and that more emphasis is placed on the optimum use of physical facilities. For many smaller and rural schools, amalgamation became a possible solution to the problem. The amalgamation of schools however, implies a drastic change in the status quo. The main aim of the study is to investigate amalgamation as ...

  3. IMPLEMENTASI ALGORITMA KRIPTOGRAFI RIVEST SHAMIR ADLEMAN (RSA DAN VIGENERE CIPHER PADA GAMBAR BITMAP 8 BIT

    Directory of Open Access Journals (Sweden)

    Andro Alif Rakhman

    2015-07-01

    Full Text Available Penggunaan informasi melalui media gambar atau citra mempunyai beberapa kelemahan, salah satunya adalah kemudahan melakukan manipulasi citra oleh pihak-pihak tertentu dengan bantuan teknologi yang berkembang sekarang ini. Upaya dalam peningkatan pengamanan pengiriman informasi melalui media gambar dan perlindungan atas hak cipta hasil karya media digital maka algoritma kriptografi dapat diterapkan untuk pengamanan citra tersebut. Pada penelitian ini, menggunakan perpaduan algoritma Rivest Shamir Adleman (RSA dan Vigenere Cipher untuk melakukan pengamanan citra. Citra yang akan digunakan yaitu file bitmap dengan kedalaman piksel 8 bit. Citra akan diolah dengan cara mengenkripsi nilai indeks warna RGB pada masing-masing piksel dengan menggunakan algoritma kriptografi RSA terlebih dahulu kemudian dilanjutkan dengan menggunakan algoritma Vigenere Cipher. Sedangkan untuk tahap pendekripsiannya dilakukan dengan menggunakan algoritma Vigenere Cipher terlebuh dahulu kemudian menggunakan algoritma kriptografi RSA. Selanjutnya dilakukan analisis pengaruh penerapan algoritma Rivest Shamir Adleman (RSA dan Vigenere Cipher pada citra yang akan diamankan, meliputi analisis ruang kunci, analisis perubahan indeks warna, dan analisis waktu proses enkripsi dan deskripsi.Pengujian yang dilakukan untuk analisis tersebut, menggunakan citra berdimensi 3840 x 2160 piksel dan ukuran file 7,91 MB dan citra berdimensi 5012 x 2819 piksel dan ukuran file 13,4 MB. Analisis ruang kunci menunjukkan bahwa citra telah berhasil didekripsikan dan secara visual pola citra kembali ke bentuk semula tanpa mengalami cacat sedikitpun. Analisis perubahan indek warna, dilihat secara visual pada hasil palette warna membuktikan bahwa metode enkripsi yang dirancang telah berhasil digunakan untuk memperbaruhi nilai indeks warna citra asli. Sedangkan dari analisis waktu proses enkripsi dan deskripsi dapat disimpulkan Rata-rata lama waktu yang dibutuhkan untuk proses dekripsi lebih lama

  4. RSA加密算法中MPI的应用%Application of MPI in RSA encryption algorithm

    Institute of Scientific and Technical Information of China (English)

    陆玉阳

    2015-01-01

    RSA加密算法在进行复杂判断和大数运算时,计算时间往往花费较多,对计算机的运行速度、存储容量等方面具有较高的要求.MPI能够提供较快的数值计算和数据处理能力,提供高性能并行计算.该文通过在RSA加密算法中MPI的应用,通过实践证明MPI并行计算可以改进RSA算法,提高加密速度、减少容量需求等.%RSA encryption algorithm in the complex judgment and operation of large Nbers, calculating the time tend to spend more, the computer run faster, have higher requirements in terms of storage capacity. MPI provides fast Nerical calculation and data processing capability, providing high performance parallel computing. Based on RSA encryption algorithm in application of MPI, MPI parallel computing can improve the RSA algorithm proved by practice, increase speed, reduce capacity requirements, and so on.

  5. Aspects of ultra-high-precision diamond machining of RSA 443 optical aluminium

    Science.gov (United States)

    Mkoko, Z.; Abou-El-Hossein, K.

    2015-08-01

    Optical aluminium alloys such as 6061-T6 are traditionally used in ultra-high precision manufacturing for making optical mirrors for aerospace and other applications. However, the optics industry has recently witnessed the development of more advanced optical aluminium grades that are capable of addressing some of the issues encountered when turning with single-point natural monocrystalline diamond cutters. The advent of rapidly solidified aluminium (RSA) grades has generally opened up new possibilities for ultra-high precision manufacturing of optical components. In this study, experiments were conducted with single-point diamond cutters on rapidly solidified aluminium RSA 443 material. The objective of this study is to observe the effects of depth of cut and feed rate at a fixed rotational speed on the tool wear rate and resulting surface roughness of diamond turned specimens. This is done to gain further understanding of the rate of wear on the diamond cutters versus the surface texture generated on the RSA 443 material. The diamond machining experiments yielded machined surfaces which are less reflective but with consistent surface roughness values. Cutting tools were observed for wear through scanning microscopy; relatively low wear pattern was evident on the diamond tool edge. The highest tool wear were obtained at higher depth of cut and increased feed rate.

  6. Introducing random safety audits (RSA) in a neonatal intensive care unit (NICU).

    LENUS (Irish Health Repository)

    Szymanska, M

    2012-01-31

    Random safety audits (RSA) have been shown to be effective in improving standards of clinical practice. 19 data collection audits were performed relating to hygiene, safe prescribing, oxygen pulse oximetry monitoring and documentation in keeping with the requirements of the new Medical Practitioners Act (MPA) 2007. Hygiene audits (range from 20\\/25 to 21\\/21 80%-100%) and safe prescribing audits (range from 23\\/25 to 25\\/25 86%-100%) achieved n=25 100% compliance with unit guidelines over a 3 month period. Compliance with oxygen pulse oximetry monitoring guideline limits improved from 4\\/27 (15%) to 9\\/16 (56%). Compliance with requirement and use of Physician IMC registration number in documentation was only 10\\/18 (56%). RSA\\'s led to improvements in hygiene and prescribing. Compliance with oxygen monitoring guideline limits highlighted the need for greater education. Awareness of legal requirements relating to documentation improved but this has not translated into a change in practice. RSA\\'s can facilitate real time quality improvement in daily clinical practice.

  7. VLSI design of an RSA encryption/decryption chip using systolic array based architecture

    Science.gov (United States)

    Sun, Chi-Chia; Lin, Bor-Shing; Jan, Gene Eu; Lin, Jheng-Yi

    2016-09-01

    This article presents the VLSI design of a configurable RSA public key cryptosystem supporting the 512-bit, 1024-bit and 2048-bit based on Montgomery algorithm achieving comparable clock cycles of current relevant works but with smaller die size. We use binary method for the modular exponentiation and adopt Montgomery algorithm for the modular multiplication to simplify computational complexity, which, together with the systolic array concept for electric circuit designs effectively, lower the die size. The main architecture of the chip consists of four functional blocks, namely input/output modules, registers module, arithmetic module and control module. We applied the concept of systolic array to design the RSA encryption/decryption chip by using VHDL hardware language and verified using the TSMC/CIC 0.35 m 1P4 M technology. The die area of the 2048-bit RSA chip without the DFT is 3.9 × 3.9 mm2 (4.58 × 4.58 mm2 with DFT). Its average baud rate can reach 10.84 kbps under a 100 MHz clock.

  8. Brightness Alteration with Interweaving Contours

    Directory of Open Access Journals (Sweden)

    Sergio Roncato

    2012-12-01

    Full Text Available Chromatic induction is observed whenever the perceived colour of a target surface shifts towards the hue of a neighbouring surface. Some vivid manifestations may be seen in a white background where thin coloured lines have been drawn (assimilation or when lines of different colours are collinear (neon effect or adjacent (watercolour to each other. This study examines a particular colour induction that manifests in concomitance with an opposite effect of colour saturation (or anti-spread. The two phenomena can be observed when a repetitive pattern is drawn in which outline thin contours intercept wider contours or surfaces, colour spreading appear to fill the surface occupied by surfaces or thick lines whereas the background traversed by thin lines is seen as brighter or filled of a saturated white. These phenomena were first observed by Bozzi (1975 and Kanizsa (1979 in figural conditions that did not allow them to document their conjunction. Here we illustrate various manifestations of this twofold phenomenon and compare its effects with the known effects of brightness and colour induction. Some conjectures on the nature of these effects are discussed.

  9. Contours, 2 Ft. Contours, Published in 2006, North Georgia College and State University.

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — This Contours dataset, was produced all or in part from LIDAR information as of 2006. It is described as '2 Ft. Contours'. Data by this publisher are often provided...

  10. NY_GOME_CONTOURS: New York Bight and Gulf of Maine bathymetric contours

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This bathymetric shapefile contains 10 m contours for the continental shelf and 100 m beyond the 200 m shelf edge. The contours have been derived from the National...

  11. NY_GOME_CONTOURS: New York Bight and Gulf of Maine bathymetric contours

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This bathymetric shapefile contains 10 m contours for the continental shelf and 100 m beyond the 200 m shelf edge. The contours have been derived from the National...

  12. Contours, Two Foot Contours, Published in 2007, Not Applicable scale, Dunn County, WI.

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — This Contours dataset, published at Not Applicable scale, was produced all or in part from LIDAR information as of 2007. It is described as 'Two Foot Contours'....

  13. Contour extracting networks in early extrastriate cortex

    NARCIS (Netherlands)

    Dumoulin, Serge O.; Hess, Robert F.; May, Keith A.; Harvey, Ben M.; Rokers, Bas; Barendregt, Martijn

    2014-01-01

    Neurons in the visual cortex process a local region of visual space, but in order to adequately analyze natural images, neurons need to interact. The notion of an ''association field'' proposes that neurons interact to extract extended contours. Here, we identify the site and properties of contour

  14. RFP for the Comet Nuclei Tour (CONTOUR)

    DEFF Research Database (Denmark)

    Jørgensen, John Leif; Madsen, Peter Buch; Betto, Maurizio

    1999-01-01

    This document describes the ASC Star Tracker (performance, functionality, requirements etc.) to The Johns Hopkins University - Applied Physics Laboratory for their Comet Nuclei TOUR (CONTOUR) Program.......This document describes the ASC Star Tracker (performance, functionality, requirements etc.) to The Johns Hopkins University - Applied Physics Laboratory for their Comet Nuclei TOUR (CONTOUR) Program....

  15. Contour extracting networks in early extrastriate cortex

    NARCIS (Netherlands)

    Dumoulin, Serge O.; Hess, Robert F.; May, Keith A.; Harvey, Ben M.; Rokers, Bas; Barendregt, Martijn

    2014-01-01

    Neurons in the visual cortex process a local region of visual space, but in order to adequately analyze natural images, neurons need to interact. The notion of an ''association field'' proposes that neurons interact to extract extended contours. Here, we identify the site and properties of contour i

  16. The stress-inducible displacement detected through RSA in non-migrating UKR.

    Science.gov (United States)

    Bragonzoni, Laura; Russo, Alessandro; Loreti, Ivano; Montagna, Luisa; Visani, Andrea; Marcacci, Maurilio

    2005-08-01

    Roentgen stereophotogrammetric analysis (RSA) under stress conditions was used to investigate possible stress-inducible displacement of the tibial component of unicompartmental knee prostheses (UKR) in which the stability was previously assessed by radiographic evaluation and standard supine RSA examinations. Sixteen patients, implanted with Duracon UNI(R) prosthesis, were selected for this study. The RSA protocol included examinations in plain upright standing posture and during execution of stress-inducing tasks in weight-bearing stance. The first follow-up was performed at an average of 14 months, and the second one at 26 months. The results showed non-negligible stress-induced rotations of the prosthetic tibial component in all the patients in most of the stress tasks performed. Rotational stress tasks and squatting turned out to be the stress conditions in which induced displacement reached the most significant values (p<0.05). These micromotions occurred mainly around the transverse axis of the knee joint and in one examination around the sagittal axis. Stress-induced translations were negligible in all the examinations. Moreover, we focused our attention on two patients suffering from inexplicable pain, and we observed a significant difference in the inducible rotation around the x-axis between these patients and the remaining fourteen. Stress-inducible displacement is a common finding in knee prostheses, but we observed that in patients with inexplicable pain, these micromotions reached values greater than the median calculated on patients without any pain. This result suggests the introduction of the stress-inducible displacement as a new parameter to be taken into consideration when analyzing the outcome of patients treated by UKR.

  17. 基于Common Lisp的RSA加密实现%RSA Encryption Based on Common Lisp Implementation

    Institute of Scientific and Technical Information of China (English)

    解晨

    2013-01-01

    著名的非对称密钥加密系统——RSA公钥加密系统,是当今流行的加密系统,其简单的实现和高效的保密性使RSA加密算法成为当下最有影响力的公钥加密算法,并且其堪称完美的理论基础使得RSA加密算法可以抵抗目前所知的所有密码攻击.该文探究了RSA加密算法的原理,并使用一门小众语言Common Lisp对RSA加密进行了实现.%Asymmetric key encryption system -- the famous RSA public key encryption system, the encryption system is popu?lar, its simple implementation and high security RSA encryption algorithm to become the most influential contemporary public-key encryption algorithm, and it is theoretical basis of perfect makes the RSA encryption algorithm can resist all known attacks. This paper discusses the principle of RSA encryption algorithm, and realizes the encryption of RSA using a minority language Common Lisp.

  18. Non-random association of the Rsa I polymorphic site 5' to the beta-globin gene with major sickle cell haplotypes.

    Science.gov (United States)

    Sharon, B; Poncz, M; Surrey, S; Schwartz, E

    1988-01-01

    There are three main African haplotypes associated with the sickle mutation on chromosome 11. We have examined an Rsa I polymorphism 550 bp 5' to the beta-globin gene to study the degree of linkage disequilibrium between this Rsa I site and the three haplotypes. This Rsa I site is contained within the 10.3 kb or less area of randomization separating the 5'- and 3'-haplotype clusters. The beta S-containing chromosomes of the Benin and Senegal haplotypes are not cut, while those of the Central African Republic are cleaved by Rsa I at this site. Possible explanations of these findings are discussed.

  19. Improved RSA cryptosystem based on the study of number theory and public key cryptosystems

    Directory of Open Access Journals (Sweden)

    Israt Jahan

    2015-01-01

    Full Text Available Security is required to transmit confidential information over the network. Security is also demanding in wide range of applications. Cryptographic algorithms play a vital role in providing the data security against malicious attacks. RSA algorithm is extensively used in the popular implementations of Public Key Infrastructures. In asymmetric key cryptography, also called Public Key cryptography, two different keys (which form a key pair are used. One key is used for encryption and only the other corresponding key must be used for decryption. No other key can decrypt the message – not even the original (i.e. the first key used for encryption. In this paper, we have proposed an improved approach of RSA algorithm using two public key pairs and using some mathematical logic rather than sending one public key d irectly.Because if an attacker has an opportunity of getting the public key componet they can find private key value by brute force search. General Terms: Cryptography, network security

  20. Fibrinogen adsorption mechanisms at the gold substrate revealed by QCM-D measurements and RSA modeling.

    Science.gov (United States)

    Kubiak, Katarzyna; Adamczyk, Zbigniew; Cieśla, Michał

    2016-03-01

    Adsorption kinetics of fibrinogen at a gold substrate at various pHs was thoroughly studied using the QCM-D method. The experimental were interpreted in terms of theoretical calculations performed according to the random sequential adsorption model (RSA). In this way, the hydration functions and water factors of fibrinogen monolayers were quantitatively evaluated at various pHs. It was revealed that for the lower range of fibrinogen coverage the hydration function were considerably lower than previously obtained for the silica sensor [33]. The lower hydration of fibrinogen monolayers on the gold sensor was attributed to its higher roughness. However, for higher fibrinogen coverage the hydration functions for both sensors became identical exhibiting an universal behavior. By using the hydration functions, the fibrinogen adsorption/desorption runs derived from QCM-D measurements were converted to the Γd vs. the time relationships. This allowed to precisely determine the maximum coverage that varied between 1.6mgm(-2) at pH 3.5 and 4.5mgm(-2) at pH 7.4 (for ionic strength of 0.15M). These results agree with theoretical eRSA modeling and previous experimental data derived by using ellipsometry, OWLS and TIRF. Various fibrinogen adsorption mechanisms were revealed by exploiting the maximum coverage data. These results allow one to develop a method for preparing fibrinogen monolayers of well-controlled coverage and molecule orientation. Copyright © 2015 Elsevier B.V. All rights reserved.

  1. Cryptanalysis and Performance Evaluation of Enhanced Threshold Proxy Signature Scheme Based on RSA for Known Signers

    Directory of Open Access Journals (Sweden)

    Raman Kumar

    2013-01-01

    Full Text Available In these days there are plenty of signature schemes such as the threshold proxy signature scheme (Kumar and Verma 2010. The network is a shared medium so that the weakness security attacks such as eavesdropping, replay attack, and modification attack. Thus, we have to establish a common key for encrypting/decrypting our communications over an insecure network. In this scheme, a threshold proxy signature scheme based on RSA, any or more proxy signers can cooperatively generate a proxy signature while or fewer of them cannot do it. The threshold proxy signature scheme uses the RSA cryptosystem to generate the private and the public key of the signers (Rivest et al., 1978. Comparison is done on the basis of time complexity, space complexity, and communication overhead. We compare the performance of four schemes (Hwang et al. (2003, Kuo and Chen (2005, Yong-Jun et al. (2007, and Li et al. (2007, with the performance of a scheme that has been proposed earlier by the authors of this paper. In the proposed scheme, both the combiner and the secret share holder can verify the correctness of the information that they are receiving from each other. Therefore, the enhanced threshold proxy signature scheme is secure and efficient against notorious conspiracy attacks.

  2. Contours--Offshore of Santa Barbara, California

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This part of SIM 3281 presents data for the bathymetric contours for several seafloor maps (see sheets 1, 2, 3, 7, 10, SIM 3281) of the Offshore of Santa Barbara...

  3. Contours--Offshore Coal Oil Point, California

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This part of SIM 3302 presents bathymetric contours for several seafloor maps of Offshore Coal Oil Point, California (vector data file is included in...

  4. Transgressive Contours--Bolinas to Pescadero, California

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This part of DS 781 presents data for the transgressive contours for the Bolinas to Pescadero, California, region. The vector file is included in...

  5. Contours-Offshore of Bodega Head, California

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This part of DS 781 presents data for the bathymetric contours for several seafloor maps of the Offshore of Bodega Head map area, California. The vector data file is...

  6. Contours--Offshore of Pacifica, California

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This part of DS 781 presents data for the bathymetric contours for several seafloor maps of the Offshore of Pacifica map area, California. The vector data file is...

  7. Contours--Drakes Bay and Vicinity, California

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This part of DS 781 presents data for the bathymetric contours for several seafloor maps of the Drakes Bay and Vicinity map area, California. The vector data file is...

  8. Contours--Monterey Canyon and Vicinity, California

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This part of DS 781 presents bathymetric contours for several seafloor maps of the Monterey Canyon and Vicinity map area, California. The raster data file is...

  9. An Active Contour for Range Image Segmentation

    OpenAIRE

    Khaldi Amine; Merouani Hayet Farida

    2012-01-01

    In this paper a new classification of range image segmentation method is proposed according to the criterion of homogeneity which obeys the segmentation, then, a deformable model-type active contour “Snake” is applied to segment range images.

  10. Contours--Offshore Refugio Beach, California

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This part of SIM 3319 presents bathymetric contours for several seafloor maps of Offshore Refugio Beach, California (vector data file is included in...

  11. Contours-Offshore of Bodega Head, California

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This part of DS 781 presents data for the bathymetric contours for several seafloor maps of the Offshore of Bodega Head map area, California. The vector data file is...

  12. Water-table contours of Nevada

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This data set consists of water-table contours for Nevada. These data were created as part of an effort to provide statewide information on water table and depth to...

  13. Contours--Offshore of Pacifica, California

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This part of DS 781 presents data for the bathymetric contours for several seafloor maps of the Offshore of Pacifica map area, California. The vector data file is...

  14. Contours--Offshore of Fort Ross, California

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This part of DS 781 presents data for the bathymetric contours for several seafloor maps of the Offshore of Fort Ross map area, California. The vector data file is...

  15. Contours Offshore of Tomales Point, California

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This part of DS 781 presents data for the bathymetric contours for several seafloor maps of the Offshore of Tomales Point map area, California. The vector data file...

  16. Contours--Offshore Santa Cruz, California

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This part of DS 781 presents data for the bathymetric contours for several seafloor maps of the Offshore Santa Cruz map area, California. The vector data file is...

  17. Contours--Offshore Pigeon Point, California

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This part of DS 781 presents data for the bathymetric contours for several seafloor maps of the Offshore Pigeon Point map area, California. The vector data file is...

  18. Contours--Offshore of Fort Ross, California

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This part of DS 781 presents data for the bathymetric contours for several seafloor maps of the Offshore of Fort Ross map area, California. The vector data file is...

  19. Contours--Offshore Scott Creek, California

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This part of DS 781 presents data for the bathymetric contours for several seafloor maps of the Offshore Scott Creek map area, California. The vector data file is...

  20. Contours--Offshore of San Francisco, California

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This part of DS 781 presents data for the bathymetric contours for several seafloor maps of the Offshore of San Francisco map area, California. The vector data file...

  1. Transgressive Contours--Bolinas to Pescadero, California

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This part of DS 781 presents data for the transgressive contours for the Bolinas to Pescadero, California, region. The vector file is included in...

  2. Contours--Offshore Scott Creek, California

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This part of DS 781 presents data for the bathymetric contours for several seafloor maps of the Offshore Scott Creek map area, California. The vector data file is...

  3. Contours--Offshore Santa Cruz, California

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This part of DS 781 presents data for the bathymetric contours for several seafloor maps of the Offshore Santa Cruz map area, California. The vector data file is...

  4. Contours--Monterey Canyon and Vicinity, California

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This part of DS 781 presents bathymetric contours for several seafloor maps of the Monterey Canyon and Vicinity map area, California. The raster data file is...

  5. Algebra Structure of RSA Arithmetic%RSA算法中的代数结构

    Institute of Scientific and Technical Information of China (English)

    司光东; 杨加喜; 谭示崇; 肖国镇

    2011-01-01

    本文首次应用二次剩余理论对RSA中的代数结构进行了研究.计算出了Zn中模n的二次剩余和二次非剩余的个数,对它们之间的关系进行了分析,并用所有二次剩余构成的群对Zn进行了分割,证明了所有陪集构成的商群是一个Klein四元群.对强RSA的结构进行了研究,证明了强RSA中存在阶为φ(n)/2的元素,并且强RSA中Zn可由三个二次非剩余的元素生成.确定了Zn中任意元素的阶,证明了Zn中所有元素阶的最大值是lcm(p-1,q-1),并且给出了如何寻找Zn中最大阶元素方法.从而解决了RSA中的代数结构.%Based on the theory of quadratic residues, the algebra structure of RSA arithmetic is researched in this paper. This work calculates numbers of quadratic residues and non-residues in the group Zn* and investigates their relationship. Z*n is divided up by the group made up with all quadratic residues in Z*n and all cosets form a quotient group of order 4 which is a Klein group.Studyed the structure of strong RSA further,it shows that the element of order φ( n)/2 exists and the group Z*n can be generated by three elements of quadratic non-residues. Let the facterization n = p · q, the order of each element can be calculated, and the biggest order of all element is lcn ( p - 1, q - 1 ) in Z*n. It also shows how to find the element of the biggest order. So the algebra structure of RSA arithmetic is solved.

  6. Decoupled active contour (DAC) for boundary detection.

    Science.gov (United States)

    Mishra, Akshaya Kumar; Fieguth, Paul W; Clausi, David A

    2011-02-01

    The accurate detection of object boundaries via active contours is an ongoing research topic in computer vision. Most active contours converge toward some desired contour by minimizing a sum of internal (prior) and external (image measurement) energy terms. Such an approach is elegant, but suffers from a slow convergence rate and frequently misconverges in the presence of noise or complex contours. To address these limitations, a decoupled active contour (DAC) is developed which applies the two energy terms separately. Essentially, the DAC consists of a measurement update step, employing a Hidden Markov Model (HMM) and Viterbi search, and then a separate prior step, which modifies the updated curve based on the relative strengths of the measurement uncertainty and the nonstationary prior. By separating the measurement and prior steps, the algorithm is less likely to misconverge; furthermore, the use of a Viterbi optimizer allows the method to converge far more rapidly than energy-based iterative solvers. The results clearly demonstrate that the proposed approach is robust to noise, can capture regions of very high curvature, and exhibits limited dependence on contour initialization or parameter settings. Compared to five other published methods and across many image sets, the DAC is found to be faster with better or comparable segmentation accuracy.

  7. Isolating contour information from arbitrary images

    Science.gov (United States)

    Jobson, Daniel J.

    1989-01-01

    Aspects of natural vision (physiological and perceptual) serve as a basis for attempting the development of a general processing scheme for contour extraction. Contour information is assumed to be central to visual recognition skills. While the scheme must be regarded as highly preliminary, initial results do compare favorably with the visual perception of structure. The scheme pays special attention to the construction of a smallest scale circular difference-of-Gaussian (DOG) convolution, calibration of multiscale edge detection thresholds with the visual perception of grayscale boundaries, and contour/texture discrimination methods derived from fundamental assumptions of connectivity and the characteristics of printed text. Contour information is required to fall between a minimum connectivity limit and maximum regional spatial density limit at each scale. Results support the idea that contour information, in images possessing good image quality, is (centered at about 10 cyc/deg and 30 cyc/deg). Further, lower spatial frequency channels appear to play a major role only in contour extraction from images with serious global image defects.

  8. Perception of illusory contours enhanced in motion

    Institute of Scientific and Technical Information of China (English)

    倪睿; 王志宏; 吴新年; 汪云九; 李东光

    2003-01-01

    Investigation on illusory contours is important for understanding the mechanisms un-derlying the object recognition of human visual system. Numerous researches have shown that illusory contours formed in motion and stereopsis are generated by the unmatched features. Here we conduct three psychophysical experiments to test if Kanizsa illusory contours are also caused by unmatched information. Different types of motion (including horizontal translation, radial ex-panding and shrinking) are utilized in the experiments. The results show that no matter under what kind of motion, when figures or background move separately illusory contours are perceived stronger, and there is no significant difference between the perceived strength in these two types of motion. However, no such enhancement of perceived strength is found when figures and background move together. It is found that the strengthened unmatched features generate the enhancement effect of illusory contour perception in motion. Thus the results suggest that the process of unmatched information in visual system is a critical step in the formation of illusory contours.

  9. Improvisation of Security aspect of Steganographic System by applying RSA Algorithm

    Directory of Open Access Journals (Sweden)

    Manoj Kumar Ramaiya

    2016-07-01

    Full Text Available The applications accessing multimedia systems and content over the internet have grown extremely in the earlier few years. Moreover, several end users or intruders can simply use tools to synthesize and modify valuable information. The safety of information over unsafe communication channel has constantly been a primary concern in the consideration of researchers. It became one of the most important problems for information technology and essential to safeguard this valuable information during transmission. It is also important to determine where and how such a multimedia file is confidential. Thus, a need exists for emerging technology that helps to defend the integrity of information and protected the intellectual property privileges of owners. Various approaches are coming up to safeguard the data from unauthorized person. Steganography and Cryptography are two different techniques for security data over communication network. The primary purpose of Cryptography is to create message concept unintelligible or ciphertext might produce suspicious in the mind of opponents. On the other hand, Steganography implant secrete message in to a cover media and hides its existence. As a normal practice, data embedding is employed in communication, image, text or multimedia contents for the purpose of copyright, authentication and digital signature etc. Both techniques provides the sufficient degree of security but are vulnerable to intruder’s attacks when used over unsecure communication channel. Attempt to combines the two techniques i.e. Cryptography and Steganography, did results in security improvement. The existing steganographic algorithms primarily focus on embedding approach with less attention to pre-processing of data which offer flexibility, robustness and high security level. Our proposed model is based on Public key cryptosystem or RSA algorithms in which RSA algorithm is used for message encryption in encoding function and the resultant

  10. Association between estrogen receptor β gene Rsa1 polymorphism and depressive disorder in peri-menopausal and menopausal women

    Institute of Scientific and Technical Information of China (English)

    YU Xue-wen; REN Yong-hui; LI Xue-cheng; GAO Cheng-ge; LI Fen; HAN Zhen; LI Xu

    2005-01-01

    Objective: To investigate estrogen receptor β (ERβ) gene Rsa1 polymorphism and concentration of estrogen, FSH and LH in serum in peri-menopausal and menopausal women with depressive disorder. Methods: Seventy-four peri-menopausal and menopausal women with depressive disorder met ICD-10 and CCMD-3 assessment criteria for depressive disorder were recruited. ERβ gene Rsa1 polymorphism was analyzed with PCR-RFLP. Serum levels of estrogen, FSH and LH were measured by magnetism-ELISA. Results: The respective frequency of ERβ gene Rsa1 polymorphism was no significant difference between women with depressive disorder and the healthy women (χ2=1.106,P>0.05). The serum level of estrogen was lower in women with depressive disorder than in the healthy women (P<0.05). No difference was found for FSH and LH between two groups. Conclusion: ERβ gene Rsa1 polymorphism may be not associated with depressive disorder in the peri-menopausal and menopausal women. The serum level of estrogen is associated with depressive disorder in the peri-menopausal and menopausal women.

  11. Three Year RSA Evaluation of Vitamin E Diffused Highly Cross-linked Polyethylene Liners and Cup Stability

    DEFF Research Database (Denmark)

    Sillesen, Nanna H; Greene, Meridith E; Nebergall, Audrey K;

    2015-01-01

    Vitamin E diffusion into highly cross-linked polyethylene (E-XLPE) is a method for enhancing oxidative stability of acetabular liners. The purpose of this study was to evaluate in vivo penetration of E-XLPE using radiostereometric analysis (RSA). Eighty-four hips were recruited into a prospective...

  12. Crystal structure of Pseudomonas aeruginosa RsaL bound to promoter DNA reaffirms its role as a global regulator involved in quorum-sensing

    Science.gov (United States)

    Kang, Huaping; Gan, Jianhua; Zhao, Jingru; Kong, Weina; Zhang, Jing; zhu, Miao; Li, Fan; Song, Yaqin; Qin, Jin; Liang, Haihua

    2017-01-01

    Pseudomonas aeruginosa possesses at least three well-defined quorum-sensing (QS) (las, rhl and pqs) systems that control a variety of important functions including virulence. RsaL is a QS repressor that reduces QS signal production and ensures homeostasis by functioning in opposition to LasR. However, its regulatory role in signal homeostasis remains elusive. Here, we conducted a ChIP-seq assay and revealed that RsaL bound to two new targets, the intergenic regions of PA2228/PA2229 and pqsH/cdpR, which are required for PQS synthesis. Deletion of rsaL reduced transcription of pqsH and cdpR, thus decreasing PQS signal production. The ΔrsaL strain exhibited increased pyocyanin production and reduced biofilm formation, which are dependent on CdpR or PqsH activity. In addition, we solved the structure of the RsaL–DNA complex at a 2.4 Å resolution. Although the overall sequence similarity is quite low, RsaL folds into a HTH-like structure, which is conserved among many transcriptional regulators. Complementation results of the rsaL knockout cells with different rsaL mutants further confirmed the critical role of the DNA-binding residues (including Arg20, Gln27, Gln38, Gly35, Ser37 and Ser42) that are essential for DNA binding. Our findings reveal new targets of RsaL and provide insight into the detailed characterization of the RsaL–DNA interaction. PMID:27924027

  13. Variation in contour and cancer of stomach

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Won Hong; Hwang, Seon Moon [Asan Medical Center, Asan (Korea, Republic of); Yoon, Kwon Ha [College of Medicine, Wonkwang Univ., Iksan (Korea, Republic of)

    1999-04-01

    There were four types of stomach contour included eutonic, hypotonic, steerhorn, and cascade. The aim of this study is to clarify relationship between incidence of stomach cancer and contour variation of the stomach. Double- contrast upper gastrointestinal study was performed in 1,546 patients, who had dyspepsia or other gastrointestinal tract symptoms. The radiographs were classified into the four types including eutonic, hypotonic, steerhorn, and cascade according to stomach contour in relation to body build. We also reviewed pathologic reports on endoscopic biopsy or surgical specimen. We studied the presence of relationship between incidence of stomach cancer and variation of stomach contour. We also examined the incidence of gastritis and gastric ulcer to the stomach contour variation. Of total 1,546 patients, eutonic stomach were 438(28.3%), hypotonic 911(58.9%), steerhorn 102(6.5%) and cascade 95(6.2%). Stomach cancer was found in 139(31.7%) of 438 eutonic stomachs, in 135(14.8%) of 911 hypotonic, in 42(41.2%) of 102 steerhorn, and in 24(36.9%) of 95 cascade (P=0.001). In hypotonic stomach, the incidence of stomach cancer was lower compared to the other three types significantly (p<0.05). Gastritis or gastric ulcer was found in 146(33.3%) of eutonic stomach, in 293(32.1%) of hypotonic, in 36(35.2%) of steerhorn, and in 26(27.3%) of cascade (p=0.640). In conclusion, gastric contour variation seems to be a factor affecting development of stomach cancer. The patients with hypotonic stomach may have lower incidence of stomach cancer than that of the other types. There was no relationship between the contour and gastric ulcer.

  14. Cryolipolysis for noninvasive body contouring: clinical efficacy and patient satisfaction

    Directory of Open Access Journals (Sweden)

    Krueger N

    2014-06-01

    Full Text Available Nils Krueger,1 Sophia V Mai,2 Stefanie Luebberding,1 Neil S Sadick3 1Rosenpark Research, Darmstadt, Germany; 2Department of Dermatology, Louisiana State University, New Orleans, LA, 3Department of Dermatology, Weill Cornell Medical College, New York, NY, USA Abstract: In recent years, a number of modalities have become available for the noninvasive reduction of adipose tissue, including cryolipolysis, radiofrequency, low-level laser, and high-intensity focused ultrasound. Each technology employs a different mechanism of action to cause apoptosis or necrosis of the targeted adipocytes. Among these technologies, cryolipolysis has not only been commercially available for the longest time, but has also been best researched including in vitro and animal models and randomized controlled clinical trials in humans. The principle behind cryolipolysis exploits the premise that adipocytes are more susceptible to cooling than other skin cells. The precise application of cold temperatures triggers apoptosis of the adipocytes, which invokes an inflammatory response and leads to slow digestion by surrounding macrophages. In clinical studies, cryolipolysis was shown to reduce subcutaneous fat at the treatment site by up to 25% after one treatment. Improvements were seen in 86% of treated subjects. At 73%, the patient satisfaction rate is higher than with other technologies used for noninvasive lipolysis. Cryolipolysis has been proven to be a very safe method for body contouring, and is accomplished with only minimal discomfort. Expected side effects are temporary erythema, bruising, and transient numbness that usually resolve within 14 days after treatment. With a prevalence of 0.1%, the most common complaint is late-onset pain, occurring 2 weeks post-procedure, which resolves without intervention. Although no procedure has been accepted as the gold standard for noninvasive body contouring as yet, cryolipolysis is considered to be both safe and efficient with a

  15. A FUZZY FILTERING MODEL FOR CONTOUR DETECTION

    Directory of Open Access Journals (Sweden)

    T.C. Rajakumar

    2011-04-01

    Full Text Available Contour detection is the basic property of image processing. Fuzzy Filtering technique is proposed to generate thick edges in two dimensional gray images. Fuzzy logic is applied to extract value for an image and is used for object contour detection. Fuzzy based pixel selection can reduce the drawbacks of conventional methods(Prewitt, Robert. In the traditional methods, filter mask is used for all kinds of images. It may succeed in one kind of image but fail in another one. In this frame work the threshold parameter values are obtained from the fuzzy histogram of the input image. The Fuzzy inference method selects the complete information about the border of the object and the resultant image has less impulse noise and the contrast of the edge is increased. The extracted object contour is thicker than the existing methods. The performance of the algorithm is tested with Peak Signal Noise Ratio(PSNR and Complex Wavelet Structural Similarity Metrics(CWSSIM.

  16. Maintaining Contour Trees of Dynamic Terrains

    DEFF Research Database (Denmark)

    Agarwal, Pankaj K.; Arge, Lars; Mølhave, Thomas

    We consider maintaining the contour tree T of a piecewise-linear triangulation M that is the graph of a time varying height function h:R2→R. We carefully describe the combinatorial change in T that happen as h varies over time and how these changes relate to topological changes in M. We present...... a kinetic data structure that maintains the contour tree of h over time. Our data structure maintains certificates that fail only when h(v)=h(u) for two adjacent vertices v and u in M, or when two saddle vertices lie on the same contour of M. A certificate failure is handled in O(log(n)) time. We also show...

  17. Coding Long Contour Shapes of Binary Objects

    Science.gov (United States)

    Sánchez-Cruz, Hermilo; Rodríguez-Díaz, Mario A.

    This is an extension of the paper appeared in [15]. This time, we compare four methods: Arithmetic coding applied to 3OT chain code (Arith-3OT), Arithmetic coding applied to DFCCE (Arith-DFCCE), Huffman coding applied to DFCCE chain code (Huff-DFCCE), and, to measure the efficiency of the chain codes, we propose to compare the methods with JBIG, which constitutes an international standard. In the aim to look for a suitable and better representation of contour shapes, our probes suggest that a sound method to represent contour shapes is 3OT, because Arithmetic coding applied to it gives the best results regarding JBIG, independently of the perimeter of the contour shapes.

  18. Conversion of contours to cartesian grids

    Energy Technology Data Exchange (ETDEWEB)

    Mann, J.; Broe, B. Riget

    2006-07-15

    A robust and efficient method of calculating a cartesian grid of heights or roughnesses from contour line maps is developed. The purpose of the grids is to serve as input for atmospheric flow solvers such as WAsP Engineering or EllipSys3D. The method builds on Delaunay triangulation constrained to include all contour segments in the triangulation. It is furthermore refined to avoid spurious flat areas produced by the Delaunay triangulation. Robust ways to extrapolate beyond the convex hull of the map points are provided. (au)

  19. Conversion of contours to cartesian grids

    DEFF Research Database (Denmark)

    Mann, Jakob; Broe, Brian Riget

    A robust and efficient method of calculating a cartesian grid of heights or roughnesses from contour line maps is developed. The purpose of the grids is to serve as input for atmospheric flow solvers such as WAsP Engineering or EllipSys3D. The method builds on Delaunay triangulation constrained t...... to include all contour segments in the triangulation. It is furthermore refined to avoid spurious flat areas produced by the Delaunay triangulation. Robust ways to extrapolate beyond the convex hull of the map points are provided....

  20. 对RSA密码系统旁路攻击的防御%Resistance against side channel attack for RSA cryptosystem

    Institute of Scientific and Technical Information of China (English)

    祝力; 谷大武; 王超

    2008-01-01

    Based on the structure of the side channel attacks (SCAs) to RSA cryptosystem can resist the fault attack andcombine with the randomization method for the message and secret exponent, a new implementation scheme of CRT-based(the Chinese remained theorem) RSA is proposed. The proposed scheme can prevent simple power analysis (SPA), differentialpower analysis (DPA) and time attack, and is compatible with the existing RSA-CRT cryptosystem as well. In addition, animprovement for resisting fault attack is proposed, which can reduce extra computation time.

  1. Contour detection by surround suppression of texture

    NARCIS (Netherlands)

    Petkov, Nicolai; Tavares, JMRS; Jorge, RMN

    2007-01-01

    Based on a keynote lecture at Complmage 2006, Coimbra, Oct. 20-21, 2006, an overview is given of our activities in modelling and using surround inhibition for contour detection. The effect of suppression of a line or edge stimulus by similar surrounding stimuli is known from visual perception studie

  2. Contours--Offshore of Carpinteria, California

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This part of SIM 3261 presents data for the bathymetric contours for several seafloor maps (see sheets 1, 2, 3, 5 [in figs. 1, 2, 3], 7, 10, SIM 3261) of the...

  3. Contours--Offshore of Santa Barbara, California

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This part of SIM 3281 presents data for the bathymetric contours for several seafloor maps (see sheets 1, 2, 3, 7, 10, SIM 3281) of the Offshore of Santa Barbara map...

  4. Maintaining Contour Trees of Dynamic Terrains

    DEFF Research Database (Denmark)

    Agarwal, Pankaj K.; Arge, Lars; Mølhave, Thomas

    We consider maintaining the contour tree T of a piecewise-linear triangulation M that is the graph of a time varying height function h:R2→R. We carefully describe the combinatorial change in T that happen as h varies over time and how these changes relate to topological changes in M. We present...

  5. An Active Contour for Range Image Segmentation

    Directory of Open Access Journals (Sweden)

    Khaldi Amine

    2012-06-01

    Full Text Available In this paper a new classification of range image segmentation method is proposed according to the criterion of homogeneity which obeys the segmentation, then, a deformable model-type active contour “Snake” is applied to segment range images.

  6. Regression Model With Elliptically Contoured Errors

    CERN Document Server

    Arashi, M; Tabatabaey, S M M

    2012-01-01

    For the regression model where the errors follow the elliptically contoured distribution (ECD), we consider the least squares (LS), restricted LS (RLS), preliminary test (PT), Stein-type shrinkage (S) and positive-rule shrinkage (PRS) estimators for the regression parameters. We compare the quadratic risks of the estimators to determine the relative dominance properties of the five estimators.

  7. Contours--Offshore of Carpinteria, California

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This part of SIM 3261 presents data for the bathymetric contours for several seafloor maps (see sheets 1, 2, 3, 5 [in figs. 1, 2, 3], 7, 10, SIM 3261) of the...

  8. Automatic contour welder incorporates speed control system

    Science.gov (United States)

    Wall, W. A., Jr.

    1968-01-01

    Speed control system maintains the welding torch of an automatic welder at a substantially constant speed. The system is particularly useful when welding contoured or unusually shaped surfaces, which cause the distance from the work surface to the weld carriage to vary in a random manner.

  9. Maintaining Contour Trees of Dynamic Terrains

    DEFF Research Database (Denmark)

    Agarwal, Pankaj K.; Mølhave, Thomas; Revsbæk, Morten;

    2015-01-01

    We study the problem of maintaining the contour tree T of a terrain Sigma, represented as a triangulated xy-monotone surface, as the heights of its vertices vary continuously with time. We characterize the combinatorial changes in T and how they relate to topological changes in Sigma. We present ...

  10. Contours--Offshore of San Gregorio, California

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This part of SIM 3306 presents data for the bathymetric contours for several seafloor maps (see sheets 1, 2, 3, 7, 10, SIM 3306) of the Offshore of San Gregorio map...

  11. Analysis of CVC roll contour and determination of roll crown

    Institute of Scientific and Technical Information of China (English)

    Guang Xu; Xianjun Liu; Jiarong Zhao; Junwei Xiong

    2007-01-01

    Mathematical analysis of continuous variable crown (CVC) roll contour used in CSP production line was conducted and the roll contour function of CVC roll was obtained. The validation with actual CVC roll contour shows that the calculation values of the roll contour function and the actual roll contour parameters given by equipment provider are the same, which proves that the roll contour function of CVC rolls given in this article is correct. The nonlinear relationship between the roll crown of CVC rolls and roll shift amounts was deduced. The concept of crown extremum was given.

  12. The hydrological impact of contour trenching in Vietnam

    Science.gov (United States)

    Pramana, K. E. R.; Ertsen, M. W.; Uhlenbrook, S.; de Laat, P.; Nonner, J.

    2009-04-01

    At the foothill in the driest rural area in Vietnam, at Ninh Thuan province, poor farmers cultivate up-land crops during the wet season. The area is about 9 hectares of deforested land with a slope up to 8% and has a geology surface of crusted sands and gravels. Water is scarce during the dry season and runs off rapidly during the wet season. Hence, to provide sustainable water resources and support crop growth, a project started in 2007 aiming introducing contour trenching. The main purpose of contour trenching is to trap run off, increase soil moisture for vegetation growth and recharge the groundwater. In order to investigate the impact of the trenches, a field monitoring program was initiated measuring rainfall, soil moisture content, surface water levels and groundwater levels. Recorded annual rainfall reached 600 mm. The groundwater levels are relatively deep and constant at -8 and -10 meters. The soil moisture content ranged from 3% at the driest condition to 37% below the trench at ponding. Water levels in trenches differed from uphill to downhill with higher levels at the first trench uphill. After ponding, water in the trenches infiltrates within a period of days. In this contribution, available field measurements are analyzed in two ways. First, runoff is analyzed. Immediately after significant rainfall events, the observed ponding levels in the trenches with defined uphill runoff areas can be related to the rainfall. The results show reduction of runoff coefficients per trench in downhill direction. Second, the two dimension numerical saturated-unsaturated model Hydrus 2-D was used to simulate the soil moisture content measurements. Model results confirm that infiltration is a quick process in this area with its loamy sand soils. Based on these analyzes, potential of contour trenches for local water retention and groundwater recharge will be discussed.

  13. Information security in data exchange between mobile devices with Android system using RSA encryption

    Directory of Open Access Journals (Sweden)

    Fernando Solís

    2017-02-01

    Full Text Available The new styles and ways of life lead to greater use of wireless networks, the mobile device being a tool for data transmission, which are susceptible to threats in the transmission channels in the network. IT security plays a very important role in guaranteeing the availability, privacy and integrity of information, one of the techniques that helps in this task is cryptography, whose foundation is to transform a message so that it is unintelligible except for those who have the Key to decipher it. The research focuses on the use of the RSA algorithm between mobile devices, the encrypted data is sent through communication channels called threads that through formulas and processes executed on the server, will help to execute the encryption and decryption of the data. To carry it out, a prototype for the exchange of data between mobile devices wirelessly was designed and implemented, conducting performance tests with three nodes to improve the security. The results show the efficiency of the algorithm and additionally its functionality, the times of encryption and decryption are fast against the sending of information without any method or algorithm used.

  14. DMAC-AN INTEGRATED ENCRYPTION SCHEME WITH RSA FOR AC TO OBSTRUCT INFERENCE ATTACKS

    Directory of Open Access Journals (Sweden)

    R. Jeeva

    2012-12-01

    Full Text Available The proposal of indistinguishable encryption in Randomized Arithmetic Coding(RAC doesn’t make the system efficient because it was not encrypting the messages it sends. It recomputes the cipher form of every messages it sends that increases not only the computational cost but also increases the response time.Floating point representation in cipher increases the difficulty in decryption side because of loss in precison.RAC doesn’t handle the inference attacks like Man-in-Middle attack,Third party attack etc. In our system, Dynamic Matrix Arithmetic Coding(DMAC using dynamic session matrix to encrypt the messages. The size of the matrix is deduced from the session key that contains ID of end users which proves the server authentication.Nonce values is represented as the public key of the opponents encrypted by the session key will be exchanged between the end users to provide mutual authentication. If the adversary try to compromise either server or end users,the other system won’t respond and the intrusion will be easily detected. we have increased the hacking complexity of AC by integrating with RSA upto 99%.

  15. Die godsdiensneutraliteitsbeginsel van die Amerikaanse demokrasie - implikasie vir onderwys in die RSA

    Directory of Open Access Journals (Sweden)

    J.G. van Staden

    1995-03-01

    Full Text Available The principle of religious neutrality in the American democracy - implications for education in the RSA In a changing, democratic educational dispensation the accommodation of various religious convictions and religious needs of the heterogenous South African population is a matter that has to be dealt with with great circumspection. Valuable lessons that can prevent distress and disruption may be learnt from the way in which the American hyper-democracy has handled the situation. Democracy is the American's predominant pre-occupation. Any attempt of any group (e.g. a religious group to grant a monopoly in state schools to religious values in special learning content and religious ceremonies and practices has always been opposed. This approach has eventually led to total neutrality as regards traditional religious convictions and practices in American state schools, resulting in the establishment of another conviction (secular humanism in state schools. Thus it seems that neutrality as regards religious convictions is not possible. Absolutism of the principle of neutrality as regards traditional religions has resulted in a degeneration of moral values. If all the religious convictions cannot be accommodated in the South African public education system, it may for South Africa, as bastion of Christian civilization, be a danger sign as has been the case in the USA.

  16. Three Year RSA Evaluation of Vitamin E Diffused Highly Cross-linked Polyethylene Liners and Cup Stability.

    Science.gov (United States)

    Sillesen, Nanna H; Greene, Meridith E; Nebergall, Audrey K; Nielsen, Poul T; Laursen, Mogens B; Troelsen, Anders; Malchau, Henrik

    2015-07-01

    Vitamin E diffusion into highly cross-linked polyethylene (E-XLPE) is a method for enhancing oxidative stability of acetabular liners. The purpose of this study was to evaluate in vivo penetration of E-XLPE using radiostereometric analysis (RSA). Eighty-four hips were recruited into a prospective 10-year RSA. This is the first evaluation of the multicenter cohort after 3-years. All patients received E-XLPE liners (E1, Biomet) and porous-titanium coated cups (Regenerex, Biomet). There was no difference (P=0.450) in median femoral head penetration into the E-XLPE liners at 3-years comparing cobalt-chrome heads (-0.028mm; inter-quartile range (IQR) - 0.065 to 0.047) with ceramic heads (-0.043mm, IQR - 0.143to0.042). The 3-year follow-up indicates minimal E-XLPE liner penetration regardless of head material and minimal early cup movement.

  17. Subsidence Contours for South Louisiana; UTM 15N NAD83; LRA (2005); [subsidence_contours

    Data.gov (United States)

    Louisiana Geographic Information Center — The GIS data shapefile represents average subsidence contour intervals (0.02 cm/year over 10,000 years) for Coastal LA derived from the following: Kulp, M.A., 2000,...

  18. The robustness and accuracy of in vivo linear wear measurements for knee prostheses based on model-based RSA.

    Science.gov (United States)

    van Ijsseldijk, E A; Valstar, E R; Stoel, B C; Nelissen, R G H H; Reiber, J H C; Kaptein, B L

    2011-10-13

    Accurate in vivo measurements methods of wear in total knee arthroplasty are required for a timely detection of excessive wear and to assess new implant designs. Component separation measurements based on model-based Roentgen stereophotogrammetric analysis (RSA), in which 3-dimensional reconstruction methods are used, have shown promising results, yet the robustness of these measurements is unknown. In this study, the accuracy and robustness of this measurement for clinical usage was assessed. The validation experiments were conducted in an RSA setup with a phantom setup of a knee in a vertical orientation. 72 RSA images were created using different variables for knee orientations, two prosthesis types (fixed-bearing Duracon knee and fixed-bearing Triathlon knee) and accuracies of the reconstruction models. The measurement error was determined for absolute and relative measurements and the effect of knee positioning and true seperation distance was determined. The measurement method overestimated the separation distance with 0.1mm on average. The precision of the method was 0.10mm (2*SD) for the Duracon prosthesis and 0.20mm for the Triathlon prosthesis. A slight difference in error was found between the measurements with 0° and 10° anterior tilt. (difference=0.08mm, p=0.04). The accuracy of 0.1mm and precision of 0.2mm can be achieved for linear wear measurements based on model-based RSA, which is more than adequate for clinical applications. The measurement is robust in clinical settings. Although anterior tilt seems to influence the measurement, the size of this influence is low and clinically irrelevant.

  19. Validation of a low-dose hybrid RSA and fluoroscopy technique: Determination of accuracy, bias and precision.

    Science.gov (United States)

    Ioppolo, James; Börlin, Niclas; Bragdon, Charles; Li, Mingguo; Price, Roger; Wood, David; Malchau, Henrik; Nivbrant, Bo

    2007-01-01

    Analyzing skeletal kinematics with radiostereometric analysis (RSA) following corrective orthopedic surgery allows the quantitative comparison of different implant designs. The purpose of this study was to validate a technique for dynamically estimating the relative position and orientation of skeletal segments using RSA and single plane X-ray fluoroscopy. Two micrometer-based in vitro phantom models of the skeletal segments in the hip and knee joints were used. The spatial positions of tantalum markers that were implanted into each skeletal segment were reconstructed using RSA. The position and orientation of each segment were determined in fluoroscopy images by minimizing the difference between the markers measured and projected in the image plane. Accuracy was determined in terms of bias and precision by analyzing the deviation between the applied displacement protocol and measured pose estimates. Measured translational accuracy was less than 100 microm parallel to the image plane and less than 700 microm in the direction orthogonal to the image plane. The measured rotational error was less than 1 degrees . Measured translational and rotational bias was not statistically significant at the 95% level of confidence. The technique allows real-time kinematic skeletal measurements to be performed on human subjects implanted with tantalum markers for quantitatively measuring the motion of normal joints and different implant designs.

  20. Implementation of Digital Signature Using Aes and Rsa Algorithms as a Security in Disposition System af Letter

    Science.gov (United States)

    Siregar, H.; Junaeti, E.; Hayatno, T.

    2017-03-01

    Activities correspondence is often used by agencies or companies, so that institutions or companies set up a special division to handle issues related to the letter management. Most of the distribution of letters using electronic media, then the letter should be kept confidential in order to avoid things that are not desirable. Techniques that can be done to meet the security aspect is by using cryptography or by giving a digital signature. The addition of asymmetric and symmetric algorithms, i.e. RSA and AES algorithms, on the digital signature had been done in this study to maintain data security. The RSA algorithm was used during the process of giving digital signature, while the AES algorithm was used during the process of encoding a message that will be sent to the receiver. Based on the research can be concluded that the additions of AES and RSA algorithms on the digital signature meet four objectives of cryptography: Secrecy, Data Integrity, Authentication and Non-repudiation.

  1. RESEARCH OF BASIFACIAL CONTOURING SCULPTURE BY MANDIBULAR ANGLE OSTECTOMY

    Institute of Scientific and Technical Information of China (English)

    FANG Jian-lin; DAI Chuan-chang; ZHU Guo-xian; ZHANG Ying; JIN Yu-qing; WANG Wei; QI Chuan-liang

    2006-01-01

    Objective Mandibular angle ostectomy is usually applied to the facial contouring sculpture.We evaluated the various techniques in order to enhance the precision and avoid unnecessary damage. Methods Before operation the area and quantity resected bone were designed according to facial measurement, mandible pantomography and orthophoria and lateral localized radiograph of skull. The Incises of mandibular angle ostectomy included intraoral, retroauricular or intraoral associated with retroauricular. Howerer, the sagittal resection of mandible outer table was necessary in all intraoral incise. Results Single mandibular angle ostectomy was not satisfactory for the patients having mandible hypertrophy with over-width basifacial contouring. Mandibular angle ostectomy combined with the sagittal resection of outer table of mandibular angle were required. Good symmetry and ap pearance were gained in 206 cases. One case had facial paralysis. Two patients occured mandibular fracture during the operation. Three cases complicated angled deformity at mandible body. Conclusion Reduction mandibuloplasty should be selected depends on varied types of mandibular angle hypertrophy before operation.

  2. USGS Elevation Contours Overlay Map Service from The National Map

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — The USGS Elevation Contours service from The National Map (TNM) consists of contours generated for the conterminous United States from 1- and 1/3 arc-second...

  3. Automatic liver contouring for radiotherapy treatment planning

    Science.gov (United States)

    Li, Dengwang; Liu, Li; Kapp, Daniel S.; Xing, Lei

    2015-09-01

    To develop automatic and efficient liver contouring software for planning 3D-CT and four-dimensional computed tomography (4D-CT) for application in clinical radiation therapy treatment planning systems. The algorithm comprises three steps for overcoming the challenge of similar intensities between the liver region and its surrounding tissues. First, the total variation model with the L1 norm (TV-L1), which has the characteristic of multi-scale decomposition and an edge-preserving property, is used for removing the surrounding muscles and tissues. Second, an improved level set model that contains both global and local energy functions is utilized to extract liver contour information sequentially. In the global energy function, the local correlation coefficient (LCC) is constructed based on the gray level co-occurrence matrix both of the initial liver region and the background region. The LCC can calculate the correlation of a pixel with the foreground and background regions, respectively. The LCC is combined with intensity distribution models to classify pixels during the evolutionary process of the level set based method. The obtained liver contour is used as the candidate liver region for the following step. In the third step, voxel-based texture characterization is employed for refining the liver region and obtaining the final liver contours. The proposed method was validated based on the planning CT images of a group of 25 patients undergoing radiation therapy treatment planning. These included ten lung cancer patients with normal appearing livers and ten patients with hepatocellular carcinoma or liver metastases. The method was also tested on abdominal 4D-CT images of a group of five patients with hepatocellular carcinoma or liver metastases. The false positive volume percentage, the false negative volume percentage, and the dice similarity coefficient between liver contours obtained by a developed algorithm and a current standard delineated by the expert group

  4. Measured In Situ Atmospheric Ambient Aerosol Size-Distributions, Particle Concentrations, and Turbulence Data for RSA TA-6 Test Range, Redstone Arsenal, AL, April-May 2015

    Science.gov (United States)

    2015-09-01

    Concentrations, and Turbulence Data for RSA TA-6 Test Range, Redstone Arsenal , AL, April–May 2015 by Kristan Gurton, Stephanie Cunningham, and...Aerosol Size-Distributions, Particle Concentrations, and Turbulence Data for RSA TA-6 Test Range, Redstone Arsenal , AL, April–May 2015 by Kristan...Redstone Arsenal , AL Approved for public release; distribution unlimited. ii REPORT DOCUMENTATION PAGE Form Approved OMB No. 0704-0188

  5. Rapid Automated Target Segmentation and Tracking on 4D Data without Initial Contours

    Directory of Open Access Journals (Sweden)

    Venkata V. Chebrolu

    2014-01-01

    Full Text Available Purpose. To achieve rapid automated delineation of gross target volume (GTV and to quantify changes in volume/position of the target for radiotherapy planning using four-dimensional (4D CT. Methods and Materials. Novel morphological processing and successive localization (MPSL algorithms were designed and implemented for achieving autosegmentation. Contours automatically generated using MPSL method were compared with contours generated using state-of-the-art deformable registration methods (using Elastix© and MIMVista software. Metrics such as the Dice similarity coefficient, sensitivity, and positive predictive value (PPV were analyzed. The target motion tracked using the centroid of the GTV estimated using MPSL method was compared with motion tracked using deformable registration methods. Results. MPSL algorithm segmented the GTV in 4DCT images in 27.0±11.1 seconds per phase (512×512 resolution as compared to 142.3±11.3 seconds per phase for deformable registration based methods in 9 cases. Dice coefficients between MPSL generated GTV contours and manual contours (considered as ground-truth were 0.865±0.037. In comparison, the Dice coefficients between ground-truth and contours generated using deformable registration based methods were 0.909 ± 0.051. Conclusions. The MPSL method achieved similar segmentation accuracy as compared to state-of-the-art deformable registration based segmentation methods, but with significant reduction in time required for GTV segmentation.

  6. Rapid Automated Target Segmentation and Tracking on 4D Data without Initial Contours.

    Science.gov (United States)

    Chebrolu, Venkata V; Saenz, Daniel; Tewatia, Dinesh; Sethares, William A; Cannon, George; Paliwal, Bhudatt R

    2014-01-01

    Purpose. To achieve rapid automated delineation of gross target volume (GTV) and to quantify changes in volume/position of the target for radiotherapy planning using four-dimensional (4D) CT. Methods and Materials. Novel morphological processing and successive localization (MPSL) algorithms were designed and implemented for achieving autosegmentation. Contours automatically generated using MPSL method were compared with contours generated using state-of-the-art deformable registration methods (using Elastix© and MIMVista software). Metrics such as the Dice similarity coefficient, sensitivity, and positive predictive value (PPV) were analyzed. The target motion tracked using the centroid of the GTV estimated using MPSL method was compared with motion tracked using deformable registration methods. Results. MPSL algorithm segmented the GTV in 4DCT images in 27.0 ± 11.1 seconds per phase (512 × 512 resolution) as compared to 142.3 ± 11.3 seconds per phase for deformable registration based methods in 9 cases. Dice coefficients between MPSL generated GTV contours and manual contours (considered as ground-truth) were 0.865 ± 0.037. In comparison, the Dice coefficients between ground-truth and contours generated using deformable registration based methods were 0.909 ± 0.051. Conclusions. The MPSL method achieved similar segmentation accuracy as compared to state-of-the-art deformable registration based segmentation methods, but with significant reduction in time required for GTV segmentation.

  7. [External contour acquisition system for radiotherapy: an original solution].

    Science.gov (United States)

    Létourneau, D; Brochet, F; Bohémier, R; Gagnon, J

    2000-01-01

    A contour acquisition system has been designed in radiotherapy at the Sagamie Hospital complex (Chicoutimi, Québec) to measure the external contours of the patients who do not need a CT exam. This measuring system can produce transversal, sagittal or coronal patient contours in the treatment position. The absolute accuracy of the system is +/- 1 mm. The contours produced by this equipment can be transferred electronically or on paper to the planning system.

  8. CUDA based high performance implementation of RSA algorithm.%RSA算法的CUDA高效实现技术

    Institute of Scientific and Technical Information of China (English)

    孙迎红; 童元满; 王志英

    2011-01-01

    As a new architecture supporting general purpose computing on GPU, Compute Unified Device Architecture(CUDA) plays an important role in massive data parallel computing. RSA is a kind of computing concentrated public key cryptographic algorithm. To improve the performance of RSA algorithm,CUDA based high performance implementation is presented in this paper. The key of CUDA implementation of RSA is large amount of independent parallel Montgomery modular multiplication thread in the kernel side. The threads organization scheme and data structure of this implementation are also presented. Besides, shared memory based performance improvement method is also presented. According to the implementation method of this paper, the performance and throughput of RSA algorithm are obtained for a CUDA GPU.The experiment results show that the CUDA implementation can achieve more than 40 times speedup in comparison with general CPU implementation of RSA.%CUDA(Compute Unified Device Architecture)作为一种支持GPU通用计算的新型计算架构,在大规模数据并行计算方面得到了广泛的应用.RSA算法是一种计算密集型的公钥密码算法,给出了基于CUDA的RSA算法并行化高效实现技术,其关键为引入大量独立并发的Montgomery模乘线程,并给出了具体的线程组织、数据存储结构以及基于共享内存的性能优化实现技术.根据RSA算法CUDA实现方法,在某款GPU上测试了RSA算法的运算性能和吞吐率.实验结果表明,与RSA算法的通用CPU实现方式相比,CUDA实现能够实现超过40倍的性能加速.

  9. CYP2E1 Rsa Ⅰ polymorphism impacts on risk of colorectal cancer association with smoking and alcohol drinking

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    AIM: To investigate associations between the Rsa Ⅰpolymorphism of CYP2E1 and risk of colorectal cancer.METHODS: A case-control study was conducted with 315 colorectal cancer cases (105 colon, 210 rectal)and 439 population-based controls in Jiangsu Province of China. Genomic DNA samples were assayed for restriction fragment length polymorphisms in CYP2E1by PCR amplification followed by digestion with Rsa Ⅰ. Information on smoking and alcohol drinking was collected using a questionnaire. Odds ratios (ORs) were estimated with an unconditional logistic model.RESULTS: The proportional distribution of the CYP2E1 Rsa Ⅰ c1/c1, c1/c2 and c2/c2 genotypes were 61.4%,35.6% and 3.0% in controls, 60.6%, 33.7% and 5.8%in colon cancer cases, and 58.4%, 34.0% and 7.7% in rectal cancer cases, respectively. A significant difference was noted between controls and rectal cancer cases (P = 0.029), the c2/c2 genotype being associated with elevated OR (adjusted age, sex and status of the smoking and alcohol drinking) for rectal cancer (1.64,95% CI, 1.12-2.41, vs c1 allele carriers), but not for colon cancer. In interaction analysis between the CYP2E1Rsa Ⅰ genotype and smoking and drinking habits, we found a significant cooperative action between the c2/c2 genotype and alcohol drinking in the sex-, age-adjusted ORs for both colon (4.74, 95% CI, 1.10-20.40) and rectal (5.75, 95% CI, 1.65-20.05) cancers. Among nonsmokers, the CYP2E1 Rsa Ⅰ c2/c2 genotype was also associated with elevated ORs in the two sites (1.95, 95%CI, 0.99-3.86 and 2.30, 95% CI, 1.32-3.99).CONCLUSION: The results of the present study suggest that the CYP2E1 c2/c2 genotype increases susceptibility to rectal cancer and the gene-environmental interactions between the CYP2E1 polymorphism and smoking or alcohol drinking exist for colorectal neoplasia in general.

  10. Edge and line oriented contour detection : State of the art

    NARCIS (Netherlands)

    Papari, Giuseppe; Petkov, Nicolai

    We present an overview of various edge and line oriented approaches to contour detection that have been proposed in the last two decades. By edge and line oriented we mean methods that do not rely on segmentation. Distinction is made between edges and contours. Contour detectors are divided in local

  11. Edge and line oriented contour detection : State of the art

    NARCIS (Netherlands)

    Papari, Giuseppe; Petkov, Nicolai

    2011-01-01

    We present an overview of various edge and line oriented approaches to contour detection that have been proposed in the last two decades. By edge and line oriented we mean methods that do not rely on segmentation. Distinction is made between edges and contours. Contour detectors are divided in local

  12. Human Lips-Contour Recognition and Tracing

    Directory of Open Access Journals (Sweden)

    Md. Hasan Tareque

    2014-01-01

    Full Text Available Human-lip detection is an important criterion for many automated modern system in present day. Like computerized speech reading, face recognition etc. system can work more precisely if human-lip can detect accurately. There are many processes for detecting human-lip. In this paper an approach is developed so that the region of a human-lip can be detected, we called it lip contour. For this a region-based Active Contour Model (ACM is introduced with watershed segmentation. In this model we used global energy terms instead of local energy terms because, global energy gives better convergence rate for malicious environment. At the time of ACM initialization by using H8 based on Lyapunov stability theory, the system gives more accurate and stable result.

  13. Maintaining Contour Trees of Dynamic Terrains

    DEFF Research Database (Denmark)

    Agarwal, Pankaj K.; Mølhave, Thomas; Revsbæk, Morten

    2015-01-01

    We study the problem of maintaining the contour tree T of a terrain Sigma, represented as a triangulated xy-monotone surface, as the heights of its vertices vary continuously with time. We characterize the combinatorial changes in T and how they relate to topological changes in Sigma. We present...... a kinetic data structure (KDS) for maintaining T efficiently. It maintains certificates that fail, i.e., an event occurs, only when the heights of two adjacent vertices become equal or two saddle vertices appear on the same contour. Assuming that the heights of two vertices of Sigma become equal only O(1......) times and these instances can be computed in O(1) time, the KDS processes O(kappa + n) events, where n is the number of vertices in Sigma and kappa is the number of events at which the combinatorial structure of T changes, and processes each event in O(log n) time. The KDS can be extended to maintain...

  14. Contours, contours 500 ft, Published in 2008, 1:24000 (1in=2000ft) scale, Box Elder County.

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — This Contours dataset, published at 1:24000 (1in=2000ft) scale, was produced all or in part from Other information as of 2008. It is described as 'contours 500 ft'....

  15. Contours, ft 10 NED contours 2, Published in 2008, 1:24000 (1in=2000ft) scale, Box Elder County.

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — This Contours dataset, published at 1:24000 (1in=2000ft) scale, was produced all or in part from Other information as of 2008. It is described as 'ft 10 NED contours...

  16. Contours, contours 100 ft, Published in 2008, 1:24000 (1in=2000ft) scale, Box Elder County.

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — This Contours dataset, published at 1:24000 (1in=2000ft) scale, was produced all or in part from Other information as of 2008. It is described as 'contours 100 ft'....

  17. Contours, contours_2ft, Published in 2007, 1:1200 (1in=100ft) scale, Dodge County, Wisconsin.

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — This Contours dataset, published at 1:1200 (1in=100ft) scale, was produced all or in part from LIDAR information as of 2007. It is described as 'contours_2ft'. Data...

  18. Contours, ft 10 NED contours 1, Published in 2008, 1:24000 (1in=2000ft) scale, Box Elder County.

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — This Contours dataset, published at 1:24000 (1in=2000ft) scale, was produced all or in part from Other information as of 2008. It is described as 'ft 10 NED contours...

  19. Contours, Tagged Vector Contours obtained from DASC, Published in 2003, 1:24000 (1in=2000ft) scale, Reno County.

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — This Contours dataset, published at 1:24000 (1in=2000ft) scale as of 2003. It is described as 'Tagged Vector Contours obtained from DASC'. Data by this publisher...

  20. Contours, contour 500 ft, Published in 2009, 1:24000 (1in=2000ft) scale, Washington County.

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — This Contours dataset, published at 1:24000 (1in=2000ft) scale, was produced all or in part from Other information as of 2009. It is described as 'contour 500 ft'....

  1. Contours, contour 50 ft, Published in 2009, 1:24000 (1in=2000ft) scale, Washington County.

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — This Contours dataset, published at 1:24000 (1in=2000ft) scale, was produced all or in part from Other information as of 2009. It is described as 'contour 50 ft'....

  2. Contours, contour 10 ft, Published in 2009, 1:24000 (1in=2000ft) scale, Washington County.

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — This Contours dataset, published at 1:24000 (1in=2000ft) scale, was produced all or in part from Other information as of 2009. It is described as 'contour 10 ft'....

  3. Body Image and Body Contouring Procedures.

    Science.gov (United States)

    Sarwer, David B; Polonsky, Heather M

    2016-10-01

    Dissatisfaction with physical appearance and body image is a common psychological phenomena in Western society. Body image dissatisfaction is frequently reported by those who have excess body weight, but also is seen in those of normal body weight. For both groups of individuals, this dissatisfaction impacts self-esteem and quality of life. Furthermore, it is believed to be the motivational catalyst to a range of appearance-enhancing behaviors, including weight loss efforts and physical activity. Body image dissatisfaction is also believed to play a role in the decision to seek the wide range of body contouring procedures offered by aesthetic physicians. Individuals who seek these procedures typically report increased body image dissatisfaction, focus on the feature they wish to alter with treatment, and often experience improvement in body image following treatment. At the same time, extreme body image dissatisfaction is a symptom of a number of recognized psychiatric disorders. These include anorexia nervosa, bulimia nervosa, and body dysmorphic disorder (BDD), all of which can contraindicate aesthetic treatment. This special topic review paper provides an overview of the relationship between body image dissatisfaction and aesthetic procedures designed to improve body contouring. The review specifically focuses on the relationship of body image and body weight, as well as the presentation of body image psychopathology that would contraindicate aesthetic surgery. The overall goal of the paper is to highlight the clinical implications of the existing research and provide suggestions for future research on the psychological aspects of body contouring procedures.

  4. Contour Estimation by Array Processing Methods

    Directory of Open Access Journals (Sweden)

    Bourennane Salah

    2006-01-01

    Full Text Available This work is devoted to the estimation of rectilinear and distorted contours in images by high-resolution methods. In the case of rectilinear contours, it has been shown that it is possible to transpose this image processing problem to an array processing problem. The existing straight line characterization method called subspace-based line detection (SLIDE leads to models with orientations and offsets of straight lines as the desired parameters. Firstly, a high-resolution method of array processing leads to the orientation of the lines. Secondly, their offset can be estimated by either the well-known method of extension of the Hough transform or another method, namely, the variable speed propagation scheme, that belongs to the array processing applications field. We associate it with the method called "modified forward-backward linear prediction" (MFBLP. The signal generation process devoted to straight lines retrieval is retained for the case of distorted contours estimation. This issue is handled for the first time thanks to an inverse problem formulation and a phase model determination. The proposed method is initialized by means of the SLIDE algorithm.

  5. Dynamic Active Contours for Visual Tracking.

    Science.gov (United States)

    Niethammer, Marc; Tannenbaum, Allen; Angenent, Sigurd

    2006-01-01

    Visual tracking using active contours is usually set in a static framework. The active contour tracks the object of interest in a given frame of an image sequence. A subsequent prediction step ensures good initial placement for the next frame. This approach is unnatural; the curve evolution gets decoupled from the actual dynamics of the objects to be tracked. True dynamical approaches exist, all being marker particle based and thus prone to the shortcomings of such particle-based implementations. In particular, topological changes are not handled naturally in this framework. The now classical level set approach is tailored for evolutions of manifolds of codimension one. However, dynamic curve evolution is at least a codimension two problem. We propose an efficient, level set based approach for dynamic curve evolution, which addresses the artificial separation of segmentation and prediction while retaining all the desirable properties of the level set formulation. It is based on a new energy minimization functional which, for the first time, puts dynamics into the geodesic active contour framework.

  6. How crowding, masking, and contour interactions are related: A developmental approach.

    Science.gov (United States)

    Doron, Ravid; Spierer, Abraham; Polat, Uri

    2015-01-01

    Young children are characterized by poor visual performances. Visual crowding, lateral interactions, and contour detection are critical functions for visual perception, context effect, and recognition that develop over the years up to maturity. The age at which the maturation's onset of the functions can be observed and the functions' underlying neural basis remain unclear. Here we used a development approach to investigate the onset of the foveal visual functions in order to learn about their neuronal basis and their relationships. We measured lateral interactions, crowding, and contour integration in participants aged 3-15 years. The results show that very young children do not exhibit collinear facilitation; rather, their vision is dominated by suppression and a high degree of crowding. Our results show sequential changes in the visual functions in parallel with the development of facilitation-that is, a significant reduction in crowding and an improved contour detection threshold. Our data suggest that the correlation between the onset age of maturation of collinear facilitation with crowding reduction and improvement of contour integration has underlying mutual neuronal mechanisms.

  7. VT 10 ft Contour Lines generated from bare earth lidar - Chittenden

    Data.gov (United States)

    Vermont Center for Geographic Information — (Link to Metadata) ElevationContours_CN10T (10ft contours) was extracted from ElevationContours_CN2T (2ft contours), which was generated by USGS from the 2004...

  8. Context modulates the ERP signature of contour integration.

    Directory of Open Access Journals (Sweden)

    Bart Machilsen

    Full Text Available We investigated how the electrophysiological signature of contour integration is changed by the context in which a contour is embedded. Specifically, we manipulated the orientations of Gabor elements surrounding an embedded shape outline. The amplitudes of early visual components over posterior scalp regions were changed by the presence of a contour, and by the orientation of elements surrounding the contour. Differences in context type had an effect on the early P1 and N1 components, but not on the later P2 component. The presence of a contour had an effect on the N1 and P2 components, but not on the earlier P1 component. A modulatory effect of context on contour integration was observed on the N1 component. These results highlight the importance of the context in which contour integration takes place.

  9. Incorporating Prior Shape into Geometric Active Contours for Face Contour Detection

    Institute of Scientific and Technical Information of China (English)

    HUANGFuzhen; SUJianbo; XIYugeng

    2004-01-01

    In this paper a new method that incorporates prior shape information into geometric active contours for face contour detection is proposed. As in general a human face can be treated as an ellipse with a little shape variation, the prior face shape is represented as an elliptical curve. By combining the prior face shape with the powerful geometric active model proposed by Chan and Vese, the improved geometric active model can retain all the advantage of the Chan-Vese model and can detect face contours in images with complex backgrounds accurately even if the image is noisy. Moreover, by implementing the new model in a variational level set framework, automatic topological changes of the model can be achieved naturally and the transformation parameters that map the face boundary to the prior shape can be roughly estimated simultaneously. The experimental results show our procedure to be eiTicient.

  10. Three-dimensional adult male head and skull contours.

    Science.gov (United States)

    Lee, Calvin; Loyd, Andre M; Nightingale, Roger; Myers, Barry S; Damon, Andrew; Bass, Cameron R

    2014-01-01

    Traumatic brain injury (TBI) is a major public health issue, affecting millions of people annually. Anthropomorphic test devices (ATDs) and finite element models (FEMs) provide a means of understanding factors leading to TBI, potentially reducing the occurrence. Thus, there is a need to ensure that these tools accurately model humans. For example, the Hybrid III was not based on 3-dimensional human head shape data. The objective of this study is to produce average head and skull contours for an average U.S. male that can be used for ATDs and FEMs. Computed tomography (CT) scans of adult male heads were obtained from a database provided by the University of Virginia Center for Applied Biomechanics. An orthographic viewer was used to extract head and skull contours from the CT scans. Landmarks were measured graphically using HyperMesh (Altair, HyperWorks). To determine the head occipital condyle (OC) centroid, surface meshes of the OCs were made and the centroid of the surfaces was calculated. The Hybrid III contour was obtained using a MicroScribe Digitizer (Solution Technologies, Inc., Oella, MD). Comparisons of the average male and ATD contours were performed using 2 methods: (1) the midsagittal and midcoronal ATD contours relative to the OC centroid were compared to the corresponding 1 SD range of the average male contours; (2) the ATD sagittal contour was translated relative to the average male sagittal contour to minimize the area between the 2 contours. Average male head and skull contours were created. Landmark measurements were made for the dorsum sellae, nasion skin, nasion bone, infraorbital foramen, and external auditory meatus, all relative to the OC centroid. The Hybrid III midsagittal contour was outside the 1 SD range for 15.2 percent of the average male head contour but only by a maximum distance of 1.5 mm, whereas the Hybrid III midcoronal head contour was outside the 1 SD range for 12.2 percent of the average male head contour by a maximum distance

  11. Automated Contour Detection for Intravascular Ultrasound Image Sequences Based on Fast Active Contour Algorithm

    Institute of Scientific and Technical Information of China (English)

    DONG Hai-yan; WANG Hui-nan

    2006-01-01

    Intravascular ultrasound can provide high-resolution real-time crosssectional images about lumen, plaque and tissue. Traditionally, the luminal border and medial-adventitial border are traced manually. This process is extremely timeconsuming and the subjective difference would be large. In this paper, a new automated contour detection method is introduced based on fast active contour model.Experimental results found that lumen and vessel area measurements after automated detection showed good agreement with manual tracings with high correlation coefficients (0.94 and 0.95, respectively) and small system difference ( -0.32 and 0.56, respectively). So it can be a reliable and accurate diagnostic tool.

  12. Hybrid antenna synthesis for reconfigurable contoured beams

    Science.gov (United States)

    Searle, A. D.; Westcott, B. S.

    1993-08-01

    A reflector illuminated by a small phased array is an attractive antenna configuration for systems requiring reconfigurable contoured beams. The use of a shaped reflector can provide control of the feed power distribution and antenna geometry. A systematic reflector synthesis technique based on geometric optics is formulated, using complex coordinate notation and illustrated by application to a simple design requirement. Results demonstrate that geometric shaping can be successfully applied to systems with distributed sources, and that significant beam reconfiguration can be achieved by phase-only control of the feed array.

  13. Alar Contour Grafts in Rhinoplasty: A Safe and Reproducible Way to Refine Alar Contour Aesthetics.

    Science.gov (United States)

    Unger, Jacob G; Roostaeian, Jason; Small, Kevin H; Pezeshk, Ronnie A; Lee, Michael R; Harris, Ryan; Rohrich, Rod J

    2016-01-01

    Alar rim deformities such as retraction, notching, collapse, and asymmetry are common problems in rhinoplasty patients. Although alar rim deformities may be improved through rhinoplasty, this area is prone to late changes because of scarring of the soft triangles and a paucity of native structural support. The purpose of this study was to analyze the effect of alar contour grafts on primary rhinoplasty. Fifty consecutive primary rhinoplasty patients with preoperative and postoperative photographs who received alar contour grafts were evaluated for alar aesthetics; 50 consecutive primary rhinoplasty patients without such grafts served as controls. Differences among alar retraction, notching, collapse, and asymmetry from anterior, lateral, and basal views were evaluated. Follow-up ranged from 1 to 4 years and was graded on a four-point scale. The average difference between the two groups' aggregate preoperative scores was 0.21 (p = 0.24). The average preoperative and postoperative scores in the nongraft group were significant for worsening retraction, notching, and collapse but insignificant for asymmetry. The preoperative and postoperative scores for the graft group were insignificant for retraction but improved significantly for notching, collapse, and asymmetry. Postoperatively, the aggregate average of the scores in the nongroup was 0.32 points worse (p Alar contour grafts have a clear and important impact on cosmetic results of primary rhinoplasty. Use of alar contour grafts has been shown to improve aesthetics, whereas there is a worsening of the measured parameters postoperatively without use of these grafts. Therapeutic, III.

  14. What is in a contour map? A region-based logical formalization of contour semantics

    Science.gov (United States)

    Usery, E. Lynn; Hahmann, Torsten

    2015-01-01

    Contours maps (such as topographic maps) compress the information of a function over a two-dimensional area into a discrete set of closed lines that connect points of equal value (isolines), striking a fine balance between expressiveness and cognitive simplicity. They allow humans to perform many common sense reasoning tasks about the underlying function (e.g. elevation).

  15. Automatic Detection of Adenocarcinoma using Active Contours

    Directory of Open Access Journals (Sweden)

    NeelapalaAnilKumar

    2013-09-01

    Full Text Available CT scan is the one of the image representation for abdomen, where the tumour to be located and specified effectively with clarity, by the medical expert. This role can be hold by using one of the image processing techniques called segmentation. Image segmentation is the technique which isolates the image into different regions to simplify the image and identify the Tumour easily. Image segmentation has been extensively studied by various approaches. This work, focus on the one of the image segmentation technique with a new regularization term that yields an unsupervised segmentation model which identifies different Tumour locations in a given CT image. Active contours form a boundary around a particular part of the image based on an energy function. The energy function may include intensity values of pixels or gradient values. Chen-Vase method of active contour algorithm is adopted for image segmentation. The segmentation is done after properly masking of CT scan image. The cancer prone area is generalized prior to the masking of the image. Effected abdomen cancer can be identified for better analysis of medical experts using image processing MATLAB tools. This paper describes a new method to detect and extract the features in CT scan images, which shows good performance in detection of difficult features. And the developed technique makes use of major image processing methods and fundamentals to detect the cancer with minimum possible human interaction.

  16. Study fidelity spatial contours of industrial robots

    Directory of Open Access Journals (Sweden)

    A. V. Ivanova

    2014-01-01

    Full Text Available The purpose of this paper to identify deviations fidelity spatial contours of industrial robots, determine the error pattern detected, and define the ways to solve the problem.The paper presents the research results of fidelity spatial contours done by Fanuc M- 710iC/50 industrial robot when moving along a predetermined path. The proposed method uses a QC20-W ballbar wireless system of Renishaw company, designed to diagnose the state of the measurement and playback linear and angular displacements of the CNC.The solutions to adapt the QC20-W ballbar system to the constructive peculiarities of industrial robots with five or more independently controlled axes are given. The stages of the preparation of diagnostic systems and software robot movements are described.According to study results of errors that arise while playing back the programmed motions of a fixed point of robot capture in three mutually perpendicular planes its practical accuracy has been defined when performing movements in a given region of the working area, thereby allowing us, eventually, to draw a conclusion on the possibility to use a robot in one technological process or another.The study has resulted in emerging the guidelines for the operation of industrial robots with five or more independently controlled axes. Using these guidelines enables us to increase the playback accuracy of the industrial robot to 0.01 mm.

  17. Security Analysis and Performance Evaluation of Enhanced Threshold Proxy Signature Scheme Based on RSA for Known Signers

    Directory of Open Access Journals (Sweden)

    Raman Kumar

    2012-08-01

    Full Text Available An efficient threshold signature scheme solves the difficulties of the receiver to proof the approval of the document from the sender as well as detecting if the file has been altered by illegitimate parties. In these days there are plenty of signature schemes such as (t,n threshold proxy signature scheme. The network is a shared medium so that the weakness security attacks such as eavesdropping, replay attack and modification attack. Thus, we have to establish a common key for encrypting/decrypting our communications over an insecure network. In this scheme, a (t,n threshold proxy signature scheme based on RSA, any t or more proxy signers can cooperatively generate a proxy signature while t-1 or fewer of them can’t do it. The threshold proxy signature scheme uses the RSA cryptosystem to generate the private and the public key of the signers. Comparison is done on the basis of time complexity, space complexity and communication overhead. We compare the performance of four schemes: Hwang et al., Wen et al., Geng et al. and Fengying et al. with the performance of a scheme that has been proposed by the authors of this article earlier. In the proposed scheme, both the combiner and the secret share holder can verify the correctness of the information that they are receiving from each other. Therefore, the enhanced threshold proxy signature scheme is secure and efficient against notorious conspiracy attacks.

  18. Predictive Modeling of Complex Contoured Composite Structures Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The existing HDWLT (pictured) contoured composite structure design, its analyses and manufacturing tools, will be used to validate key analyses inputs through...

  19. A new algorithm of brain volume contours segmentation

    Institute of Scientific and Technical Information of China (English)

    吴建明; 施鹏飞

    2003-01-01

    This paper explores brain CT slices segmentation technique and some related problems, including contours segmentation algorithms, edge detector, algorithm evaluation and experimental results. This article describes a method for contour-based segmentation of anatomical structures in 3D medical data sets. With this method, the user manually traces one or more 2D contours of an anatomical structure of interest on parallel planes arbitrarily cutting the data set. The experimental results showes the segmentation based on 3D brain volume and 2D CT slices. The main creative contributions in this paper are: (1) contours segmentation algorithm; (2) edge detector; (3) algorithm evaluation.

  20. Probabilistic contour extraction based on shape prior model

    Institute of Scientific and Technical Information of China (English)

    FAN Xin; LIANG De-qun

    2005-01-01

    Statistical shape prior model is employed to construct the dynamics in probabilistic contour estimation.By applying principal component analysis,plausible shape samples are efficiently generated to predict contour samples.Based on the shape-dependent dynamics and probabilistic image model,a particle filter is used to estimate the contour with a specific shape.Compared with the deterministic approach with shape information,the proposed method is simple yet more effective in extracting contours from images with shape variations and occlusion.

  1. Effects of Spatial Frequency Similarity and Dissimilarity on Contour Integration.

    Directory of Open Access Journals (Sweden)

    Malte Persike

    Full Text Available We examined the effects of spatial frequency similarity and dissimilarity on human contour integration under various conditions of uncertainty. Participants performed a temporal 2AFC contour detection task. Spatial frequency jitter up to 3.0 octaves was applied either to background elements, or to contour and background elements, or to none of both. Results converge on four major findings. (1 Contours defined by spatial frequency similarity alone are only scarcely visible, suggesting the absence of specialized cortical routines for shape detection based on spatial frequency similarity. (2 When orientation collinearity and spatial frequency similarity are combined along a contour, performance amplifies far beyond probability summation when compared to the fully heterogenous condition but only to a margin compatible with probability summation when compared to the fully homogenous case. (3 Psychometric functions are steeper but not shifted for homogenous contours in heterogenous backgrounds indicating an advantageous signal-to-noise ratio. The additional similarity cue therefore not so much improves contour detection performance but primarily reduces observer uncertainty about whether a potential candidate is a contour or just a false positive. (4 Contour integration is a broadband mechanism which is only moderately impaired by spatial frequency dissimilarity.

  2. India-Pakistan: Contours of Relationship

    Directory of Open Access Journals (Sweden)

    Devika Mittal

    2016-06-01

    Full Text Available Even after about 70 years of separation, India and Pakistan continue to live in the prison of the past. The rhetoric of partition is still alive in the memory of the people of both the countries. They have constructed fixed, unchanging and competing images for each other. While Pakistan became an Islamic Republic, India adopted secularism, thereby, negating the two-nation theory. The ‘differences’ along with memories of partition has made Indian and Pakistani to remain in permanent hostile situation. The leaders of the two countries try to settle their disputes but fails because of lack of support from their social and political institutions. Since its coming into power in 2014, the NDA government under the Indian Prime Minister, Mr. Narendra Modi has managed to engage the Pakistani establishment, despite many problems between the two countries. This article tries to highlight upon the contours of relationships post-2014.

  3. Automatic Contour Extraction from 2D Image

    Directory of Open Access Journals (Sweden)

    Panagiotis GIOANNIS

    2011-03-01

    Full Text Available Aim: To develop a method for automatic contour extraction from a 2D image. Material and Method: The method is divided in two basic parts where the user initially chooses the starting point and the threshold. Finally the method is applied to computed tomography of bone images. Results: An interesting method is developed which can lead to a successful boundary extraction of 2D images. Specifically data extracted from a computed tomography images can be used for 2D bone reconstruction. Conclusions: We believe that such an algorithm or part of it can be applied on several other applications for shape feature extraction in medical image analysis and generally at computer graphics.

  4. CMOS image sensor with contour enhancement

    Science.gov (United States)

    Meng, Liya; Lai, Xiaofeng; Chen, Kun; Yuan, Xianghui

    2010-10-01

    Imitating the signal acquisition and processing of vertebrate retina, a CMOS image sensor with bionic pre-processing circuit is designed. Integration of signal-process circuit on-chip can reduce the requirement of bandwidth and precision of the subsequent interface circuit, and simplify the design of the computer-vision system. This signal pre-processing circuit consists of adaptive photoreceptor, spatial filtering resistive network and Op-Amp calculation circuit. The adaptive photoreceptor unit with a dynamic range of approximately 100 dB has a good self-adaptability for the transient changes in light intensity instead of intensity level itself. Spatial low-pass filtering resistive network used to mimic the function of horizontal cell, is composed of the horizontal resistor (HRES) circuit and OTA (Operational Transconductance Amplifier) circuit. HRES circuit, imitating dendrite of the neuron cell, comprises of two series MOS transistors operated in weak inversion region. Appending two diode-connected n-channel transistors to a simple transconductance amplifier forms the OTA Op-Amp circuit, which provides stable bias voltage for the gate of MOS transistors in HRES circuit, while serves as an OTA voltage follower to provide input voltage for the network nodes. The Op-Amp calculation circuit with a simple two-stage Op-Amp achieves the image contour enhancing. By adjusting the bias voltage of the resistive network, the smoothing effect can be tuned to change the effect of image's contour enhancement. Simulations of cell circuit and 16×16 2D circuit array are implemented using CSMC 0.5μm DPTM CMOS process.

  5. 32 CFR 707.5 - Underway replenishment contour lights.

    Science.gov (United States)

    2010-07-01

    ... 32 National Defense 5 2010-07-01 2010-07-01 false Underway replenishment contour lights. 707.5... RULES WITH RESPECT TO ADDITIONAL STATION AND SIGNAL LIGHTS § 707.5 Underway replenishment contour lights... underway replenishment operations, either red or blue lights at delivery-ship-deck-edge extremities....

  6. A bit-level systolic array for digital contour smoothing

    NARCIS (Netherlands)

    Petkov, Nikolai; Sloboda, Fridrich

    1989-01-01

    Linear operators for digital contour smoothing are described. These operators are defined by circulant Toeplitz matrices and allow to smooth digital contours in the least-squares sense. They minimize the undersampling, digitizing and quantizing error and allow to calculate invariants, such as curvat

  7. Compressing industrial computed tomography images by means of contour coding

    Science.gov (United States)

    Jiang, Haina; Zeng, Li

    2013-10-01

    An improved method for compressing industrial computed tomography (CT) images is presented. To have higher resolution and precision, the amount of industrial CT data has become larger and larger. Considering that industrial CT images are approximately piece-wise constant, we develop a compression method based on contour coding. The traditional contour-based method for compressing gray images usually needs two steps. The first is contour extraction and then compression, which is negative for compression efficiency. So we merge the Freeman encoding idea into an improved method for two-dimensional contours extraction (2-D-IMCE) to improve the compression efficiency. By exploiting the continuity and logical linking, preliminary contour codes are directly obtained simultaneously with the contour extraction. By that, the two steps of the traditional contour-based compression method are simplified into only one. Finally, Huffman coding is employed to further losslessly compress preliminary contour codes. Experimental results show that this method can obtain a good compression ratio as well as keeping satisfactory quality of compressed images.

  8. Influence of Endwall Contouring on the Secondary Flow in Turbine Nozzle Guide Vane

    Institute of Scientific and Technical Information of China (English)

    SUN Da-wei; QIAO Wei-yang; XU Kai-fu

    2009-01-01

    Numerical simulations are carried out to investigate the effect of the endwall contouring on the secondary flow in turbine nozzle guide vane. The three contoured cascades with the same contouring profile and the different positions where the contoured profile locates at are researched. The results show that the contouring configuration can reduce the aerodynamic losses of the cascade. The flat side takes advantage of a stronger decrease of the losses, compared to the contoured side. The contouring configuration can also inhibit the secondary flow. The contoured cascade in which the contouring profile starts upstream of the airfoil, ends at the middle of the airfoil has the best effect of improving secondary flow.

  9. Contour polygonal approximation using shortest path in networks

    CERN Document Server

    Backes, André Ricardo; Bruno, Odemir Martinez

    2013-01-01

    Contour polygonal approximation is a simplified representation of a contour by line segments, so that the main characteristics of the contour remain in a small number of line segments. This paper presents a novel method for polygonal approximation based on the Complex Networks theory. We convert each point of the contour into a vertex, so that we model a regular network. Then we transform this network into a Small-World Complex Network by applying some transformations over its edges. By analyzing of network properties, especially the geodesic path, we compute the polygonal approximation. The paper presents the main characteristics of the method, as well as its functionality. We evaluate the proposed method using benchmark contours, and compare its results with other polygonal approximation methods.

  10. Tensor-SIFT based Earth Mover's Distance for Contour Tracking

    CERN Document Server

    Li, Peihua

    2010-01-01

    Contour tracking in adverse environments is a challenging problem due to cluttered background, illumination variation, occlusion, and noise, among others. This paper presents a robust contour tracking method by contributing to some of the key issues involved, including (a) a region functional formulation and its optimization; (b) design of a robust and effective feature; and (c) development of an integrated tracking algorithm. First, we formulate a region functional based on robust Earth Mover's distance (EMD) with kernel density for distribution modeling, and propose a two-phase method for its optimization. In the first phase, letting the candidate contour be fixed, we express EMD as the transportation problem and solve it by the simplex algorithm. Next, using the theory of shape derivative, we make a perturbation analysis of the contour around the best solution to the transportation problem. This leads to a partial differential equation (PDE) that governs the contour evolution. Second, we design a novel and...

  11. Contour-Based Surface Reconstruction using MPU Implicit Models.

    Science.gov (United States)

    Braude, Ilya; Marker, Jeffrey; Museth, Ken; Nissanov, Jonathan; Breen, David

    2007-03-01

    This paper presents a technique for creating a smooth, closed surface from a set of 2D contours, which have been extracted from a 3D scan. The technique interprets the pixels that make up the contours as points in ℝ(3) and employs Multi-level Partition of Unity (MPU) implicit models to create a surface that approximately fits to the 3D points. Since MPU implicit models additionally require surface normal information at each point, an algorithm that estimates normals from the contour data is also described. Contour data frequently contains noise from the scanning and delineation process. MPU implicit models provide a superior approach to the problem of contour-based surface reconstruction, especially in the presence of noise, because they are based on adaptive implicit functions that locally approximate the points within a controllable error bound. We demonstrate the effectiveness of our technique with a number of example datasets, providing images and error statistics generated from our results.

  12. Contour integration and segmentation with a new lateral connections model

    Science.gov (United States)

    Cai, Chao

    2011-11-01

    Automatically target contour detection from cluttered scenes is a very difficult task for computer vision. Humans, however, have a much better background suppress ability. The preceding models could not implement such a task very well. In this letter, an effective contour integration method based on human visual perception mechanism is proposed. The algorithm combines the properties of primary visual cortex and psychology researching results to simulate the contour perception of the V1 cortex. The new lateral connection based computational model have a better texture suppress ability, while, target's contour is enhanced. Compared with traditional methods, experiments show that the new method implement a more reasonable simulation of the V1 function structure, availably enhance the target's contour while suppress the cluttered background, obtain a balance between over and lose detection, besides, it has better accuracy with less computational complexity and time-consuming.

  13. CYP2E1PstI/RsaI polymorphism and interaction with tobacco, alcohol and GSTs in gastric cancer susceptibility: A meta-analysis of the literature.

    NARCIS (Netherlands)

    S. Boccia (Stefania); S. de Lauretis (Angelo); F. Gianfagna (Francesco); C.M. van Duijn (Cock); G. Ricciardi (Gualtiero)

    2007-01-01

    textabstractStudies investigating the association between cytochrome P450 2E1 (CYP2E1) 5'-flanking region (PstI/RsaI) polymorphism and gastric cancer risk report conflicting results. The rationale for this meta-analysis was to determine whether CYP2E1*2 (c2) variant allele of CYP2E1 increases

  14. Directed random polymers via nested contour integrals

    Science.gov (United States)

    Borodin, Alexei; Bufetov, Alexey; Corwin, Ivan

    2016-05-01

    We study the partition function of two versions of the continuum directed polymer in 1 + 1 dimension. In the full-space version, the polymer starts at the origin and is free to move transversally in R, and in the half-space version, the polymer starts at the origin but is reflected at the origin and stays in R-. The partition functions solve the stochastic heat equation in full-space or half-space with mixed boundary condition at the origin; or equivalently the free energy satisfies the Kardar-Parisi-Zhang equation. We derive exact formulas for the Laplace transforms of the partition functions. In the full-space this is expressed as a Fredholm determinant while in the half-space this is expressed as a Fredholm Pfaffian. Taking long-time asymptotics we show that the limiting free energy fluctuations scale with exponent 1 / 3 and are given by the GUE and GSE Tracy-Widom distributions. These formulas come from summing divergent moment generating functions, hence are not mathematically justified. The primary purpose of this work is to present a mathematical perspective on the polymer replica method which is used to derive these results. In contrast to other replica method work, we do not appeal directly to the Bethe ansatz for the Lieb-Liniger model but rather utilize nested contour integral formulas for moments as well as their residue expansions.

  15. Refined contour analysis of giant unilamellar vesicles

    Science.gov (United States)

    Pécréaux, J.; Döbereiner, H.-G.; Prost, J.; Joanny, J.-F.; Bassereau, P.

    2004-03-01

    The fluctuation spectrum of giant unilamellar vesicles is measured using a high-resolution contour detection technique. An analysis at higher q vectors than previously achievable is now possible due to technical improvements of the experimental setup and of the detection algorithm. The global fluctuation spectrum is directly fitted to deduce the membrane tension and the bending modulus of lipid membranes. Moreover, we show that the planar analysis of fluctuations is valid for spherical objects, even at low wave vectors. Corrections due to the integration time of the video camera and to the section of a 3D object by the observation plane are introduced. A precise calculation of the error bars has been done in order to provide reliable error estimate. Eventually, using this technique, we have measured bending moduli for EPC, SOPC and \\chem{SOPC:CHOL} membranes confirming previously published values. An interesting application of this technique can be the measurement of the fluctuation spectra for non-equilibrium membranes, such as “active membranes”.

  16. Between fall and fall-rise: substance-function relations in German phrase-final intonation contours.

    Science.gov (United States)

    Ambrazaitis, Gilbert

    2005-01-01

    This study investigates an intonation contour of German whose status has not been established yet: a globally falling contour with a slight rise at the very end of the phrase (FSR). The contour may be said to lie on a phonetic continuum between falling (F) and falling-rising (FR) contours. It is hypothesized that F, FR and FSR differ with respect to their communicative functions: F is terminal, FR is non-terminal, and FSR is pseudo-terminal, respectively. The hypotheses were tested in two steps. First, measurements in a labelled corpus of spontaneous speech provided the necessary background information on the phonetics of the contours. In the second step, the general hypothesis was approached in a perceptual experiment using the paradigm of a semantic differential: 49 listeners judged 17 systematically generated stimuli on nine semantic scales, such as 'impolite/polite'. The hypotheses were generally confirmed. Both F and FSR were associated with a conclusive statement, while FR was more likely to be judged as marking a question. FSR differs from F in that it does not express features such as categoricalness, dominance or impoliteness. The results are interpreted as an instance of the frequency code: the addition of a slight rise means avoidance of extremely low F(0); the functional consequence is a reduction of communicated dominance.

  17. Hybrid Parallel Contour Trees, Version 1.0

    Energy Technology Data Exchange (ETDEWEB)

    2017-01-03

    A common operation in scientific visualization is to compute and render a contour of a data set. Given a function of the form f : R^d -> R, a level set is defined as an inverse image f^-1(h) for an isovalue h, and a contour is a single connected component of a level set. The Reeb graph can then be defined to be the result of contracting each contour to a single point, and is well defined for Euclidean spaces or for general manifolds. For simple domains, the graph is guaranteed to be a tree, and is called the contour tree. Analysis can then be performed on the contour tree in order to identify isovalues of particular interest, based on various metrics, and render the corresponding contours, without having to know such isovalues a priori. This code is intended to be the first data-parallel algorithm for computing contour trees. Our implementation will use the portable data-parallel primitives provided by Nvidia’s Thrust library, allowing us to compile our same code for both GPUs and multi-core CPUs. Native OpenMP and purely serial versions of the code will likely also be included. It will also be extended to provide a hybrid data-parallel / distributed algorithm, allowing scaling beyond a single GPU or CPU.

  18. The prevalence of body contouring surgery after gastric bypass surgery.

    Science.gov (United States)

    Kitzinger, Hugo B; Abayev, Sara; Pittermann, Anna; Karle, Birgit; Kubiena, Harald; Bohdjalian, Arthur; Langer, Felix B; Prager, Gerhard; Frey, Manfred

    2012-01-01

    As bariatric surgery has become more popular, more patients are undergoing body contouring surgery after massive weight loss. Many of the surgical procedures performed on the massive weight loss patient are complex and labor-intensive. Therefore, the plastic surgery unit needs to be prepared for a patient's demand. Little literature is available on how frequently patients who have undergone gastric bypass surgery receive body contouring surgery. Two hundred fifty-two subjects (out of 425 who were mailed the questionnaire) who had undergone gastric bypass surgery between 2003 and 2009 completed the questionnaire, which obtained information on body image satisfaction and frequency of body contouring surgery after massive weight loss. Of all patients, 74% desire a body contouring surgery after gastric bypass surgery. Fifty-three patients (21%) have undergone a total of 61 body contouring procedures. The most common were abdominoplasties (59%), followed by lower body lifts (20%). In contrast to a positive judgment of the general aspect of the body image satisfaction after massive weight loss, both genders are unsatisfied with body areas like abdomen/waist, breast, and thighs. Paralleling the increasing use of bariatric surgery, there is a high demand for body contouring surgery. A huge disparity exists between the number of subjects who desire a body contouring surgery and those who actually received it.

  19. GPU based contouring method on grid DEM data

    Science.gov (United States)

    Tan, Liheng; Wan, Gang; Li, Feng; Chen, Xiaohui; Du, Wenlong

    2017-08-01

    This paper presents a novel method to generate contour lines from grid DEM data based on the programmable GPU pipeline. The previous contouring approaches often use CPU to construct a finite element mesh from the raw DEM data, and then extract contour segments from the elements. They also need a tracing or sorting strategy to generate the final continuous contours. These approaches can be heavily CPU-costing and time-consuming. Meanwhile the generated contours would be unsmooth if the raw data is sparsely distributed. Unlike the CPU approaches, we employ the GPU's vertex shader to generate a triangular mesh with arbitrary user-defined density, in which the height of each vertex is calculated through a third-order Cardinal spline function. Then in the same frame, segments are extracted from the triangles by the geometry shader, and translated to the CPU-side with an internal order in the GPU's transform feedback stage. Finally we propose a ;Grid Sorting; algorithm to achieve the continuous contour lines by travelling the segments only once. Our method makes use of multiple stages of GPU pipeline for computation, which can generate smooth contour lines, and is significantly faster than the previous CPU approaches. The algorithm can be easily implemented with OpenGL 3.3 API or higher on consumer-level PCs.

  20. Adaptive Contour Model for Real-Time Foreground Detection

    Institute of Scientific and Technical Information of China (English)

    HUANG Ying; DING Xiaoqing

    2005-01-01

    A multiscale foreground detection method was developed to segment moving objects from a stationary background. The algorithm is based on a fixed-mesh-based contour model, which starts at the bounding box of the difference map between an input image and its background and ends at a final contour. An adaptive algorithm was developed to calculate an appropriate energy threshold to control the contours to identify the foreground silhouettes. Experiments show that this method more successfully ignores the negative influence of image noise to obtain an accurate foreground map than other foreground detection algorithms. Most shadow pixels are also eliminated by this method.

  1. Details of Side Load Test Data and Analysis for a Truncated Ideal Contour Nozzle and a Parabolic Contour Nozzle

    Science.gov (United States)

    Ruf, Joseph H.; McDaniels, David M.; Brown, Andrew M.

    2010-01-01

    Two cold flow subscale nozzles were tested for side load characteristics during simulated nozzle start transients. The two test article contours were a truncated ideal and a parabolic. The current paper is an extension of a 2009 AIAA JPC paper on the test results for the same two nozzle test articles. The side load moments were measured with the strain tube approach in MSFC s Nozzle Test Facility. The processing techniques implemented to convert the strain gage signals into side load moment data are explained. Nozzle wall pressure profiles for separated nozzle flow at many NPRs are presented and discussed in detail. The effect of the test cell diffuser inlet on the parabolic nozzle s wall pressure profiles for separated flow is shown. The maximum measured side load moments for the two contours are compared. The truncated ideal contour s peak side load moment was 45% of that of the parabolic contour. The calculated side load moments, via mean-plus-three-standard-deviations at each nozzle pressure ratio, reproduced the characteristics and absolute values of measured maximums for both contours. The effect of facility vibration on the measured side load moments is quantified and the effect on uncertainty is calculated. The nozzle contour designs are discussed and the impact of a minor fabrication flaw in the nozzle contours is explained.

  2. Bathymetric Contours for Prairie Rose Lake, Shelby County, Iowa

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This data set consists of digital bathymetry contours for Prairie Rose Lake in Shelby Co., Iowa. The U.S. Geological Survey conducted a bathymetric survey of...

  3. Bathymetric Contours for Lake Minnewashta, Dickinson County, Iowa

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This data set consists of digital bathymetry contours for Lake Minnewashta in Dickinson Co., Iowa. The U.S. Geological Survey conducted a bathymetric survey of Lake...

  4. Bathymetric Contours for Littlefield Lake, Audubon County, Iowa

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This data set consists of digital bathymetry contours for Littlefield Lake in Audubon Co., Iowa. The U.S. Geological Survey conducted a bathymetric survey of...

  5. Bathymetric Contours for Nine Eagles Lake, Decatur County, Iowa

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This data set consists of digital bathymetry contours for Nine Eagles Lake in Decatur Co., Iowa. The U.S. Geological Survey conducted a bathymetric survey of Nine...

  6. Transgressive Contours--Salt Point to Drakes Bay, California

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This part of DS 781 presents data for the transgressive contours for the Salt Point to Drakes Bay, California, region. The vector file is included in...

  7. Contours--Offshore of Salt Point Map Area, California

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This part of DS 781 presents data for the bathymetric contours for several seafloor maps of the Offshore of Salt Point map area, California. The vector data file is...

  8. Transgressive Contours--Pigeon Point to South Monterey Bay, California

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This part of DS 781 presents data for the transgressive contours for the Pigeon Point to South Monterey Bay, California, region. The vector file is included in...

  9. Contours--Offshore of Half Moon Bay, California

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This part of DS 781 presents data for the bathymetric contours for several seafloor maps of the Offshore of Half Moon map area, California. The vector data file is...

  10. Shape reconstruction from apparent contours theory and algorithms

    CERN Document Server

    Bellettini, Giovanni; Paolini, Maurizio

    2015-01-01

    Motivated by a variational model concerning the depth of the objects in a picture and the problem of hidden and illusory contours, this book investigates one of the central problems of computer vision: the topological and algorithmic reconstruction of a smooth three dimensional scene starting from the visible part of an apparent contour. The authors focus their attention on the manipulation of apparent contours using a finite set of elementary moves, which correspond to diffeomorphic deformations of three dimensional scenes. A large part of the book is devoted to the algorithmic part, with implementations, experiments, and computed examples. The book is intended also as a user's guide to the software code appcontour, written for the manipulation of apparent contours and their invariants. This book is addressed to theoretical and applied scientists working in the field of mathematical models of image segmentation.

  11. MAP Estimation of Chin and Cheek Contours in Video Sequences

    Directory of Open Access Journals (Sweden)

    Kampmann Markus

    2004-01-01

    Full Text Available An algorithm for the estimation of chin and cheek contours in video sequences is proposed. This algorithm exploits a priori knowledge about shape and position of chin and cheek contours in images. Exploiting knowledge about the shape, a parametric 2D model representing chin and cheek contours is introduced. Exploiting knowledge about the position, a MAP estimator is developed taking into account the observed luminance gradient as well as a priori probabilities of chin and cheek contours positions. The proposed algorithm was tested with head and shoulder video sequences (image resolution CIF. In nearly 70% of all investigated video frames, a subjectively error free estimation could be achieved. The 2D estimate error is measured as on average between 2.4 and .

  12. Bathymetric Contours for Upper Gar Lake, Dickinson County, Iowa

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This data set consists of digital bathymetry contours for Upper Gar Lake in Dickinson Co., Iowa. The U.S. Geological Survey conducted a bathymetric survey of Upper...

  13. Bathymetric Contours for Lake Darling, Washington County, Iowa

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This data set consists of digital bathymetry contours for Lake Darling in Washington Co., Iowa. The U.S. Geological Survey conducted a bathymetric survey of Lake...

  14. Contours Offshore of Point Reyes Map Map Area, California

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This part of DS 781 presents data for the bathymetric contours for several seafloor maps of the Offshore of Point Reyes map area, California. The vector data file is...

  15. Transgressive Contours--Pigeon Point to South Monterey Bay, California

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This part of DS 781 presents data for the transgressive contours for the Pigeon Point to South Monterey Bay, California, region. The vector file is included in...

  16. Using mathematical morphology to determine left ventricular contours

    Energy Technology Data Exchange (ETDEWEB)

    Pladellorens, J. (Universitat Politecnica de Catalunya (Spain). Dept. d' Optica i Optometria); Serrat, J. (Universitat Autonoma de Barcelona (Spain). Dept. d' Informatica); Castell, A. (Hospital de la Vall d' Hebro, Barcelona (Spain). Dept. de Medicina Nuclear); Yzuel, M.J. (Universitat Autonoma de Barcelona (Spain). Dept. de Fisica)

    1993-12-01

    Mathematical morphology is used for the determination of left ventricular contours in scintigraphic images using multigated radionuclide angiography. The authors developed a completely automatic method that first restores the image with a Wiener filter, then finds the region where the left ventricle is contained, and finally segments the left ventricle contour and a background zone. The contours depend on the values of the parameters that appear in the mathematical morphology method, which are related to the height and the slope of the count distribution. Results obtained with this method are compared with the contours and the background zones outlined by experts on the basis of the number of counts, and the authors study the values of the parameters with which optimum correlation is obtained. (author).

  17. A historical note on illusory contours in shadow writing.

    Science.gov (United States)

    Vezzani, Stefano; Marino, Barbara F M

    2009-01-01

    It is widely accepted that illusory contours have been first displayed and discussed by Schumann (1900, Zeitschrift für Psychologie und Physiologie der Sinnesorgane 23 1-32). Here we show that, before him, Jastrow (1899, Popular Science Monthly 54 299-312) produced illusory contours consisting of a shadow word. A brief history of shadow writing in psychological literature from Jastrow to Brunswik is presented, in which the contributions of Pillsbury, Warren, Koffka, and Benussi are examined.

  18. Contour Detection Using Cost-Sensitive Convolutional Neural Networks

    OpenAIRE

    Hwang, Jyh-Jing; Liu, Tyng-Luh

    2014-01-01

    We address the problem of contour detection via per-pixel classifications of edge point. To facilitate the process, the proposed approach leverages with DenseNet, an efficient implementation of multiscale convolutional neural networks (CNNs), to extract an informative feature vector for each pixel and uses an SVM classifier to accomplish contour detection. The main challenge lies in adapting a pre-trained per-image CNN model for yielding per-pixel image features. We propose to base on the Den...

  19. Upper Arm Contouring with Brachioplasty after Massive Weight Loss

    Directory of Open Access Journals (Sweden)

    Hyun Ho Han

    2014-05-01

    Full Text Available Background As the obese population increases in Korea, the number of patients who are trying to lose weight has been increasing steadily. In these patients, skin laxity and deformation of the body contour occurs, which could possibly be corrected by various body contouring surgeries. Here, we introduce the brachioplasty method and our experience of various body contouring surgeries performed in our center. Methods From November 2009 to August 2011, five cases of brachioplasty were performed. When the patient presented with sagging of the lateral inframammary crease and bat wing deformity in the axilla, extended brachioplasty was performed; in this case, the deformation of the axilla and lateral chest was corrected at the same time. A traditional brachioplasty was performed when contouring was needed only for skin laxity in the upper arm. Results Complications, such as hematomas or nerve injuries, were not evident. Some patients experienced partial wound dehiscence due to tension or hypertrophic scars found during the follow-up. In general, all of the patients were satisfied with the improvement in their upper arm contour. Conclusions Given the demands for body contouring surgery, the number of brachioplasty surgical procedures is expected to increase significantly, with abdominoplasty comprising a large portion of these surgeries. For the brachioplasty procedure, preparation and preoperative consultation regarding design of the surgery by experienced surgeons was important to prevent complications such as nerve damage or hematoma formation.

  20. The Development of Contour Processing: Evidence from Physiology and Psychophysics

    Directory of Open Access Journals (Sweden)

    Gemma eTaylor

    2014-07-01

    Full Text Available Object perception and pattern vision depend fundamentally upon the extraction of contours from the visual environment. In adulthood, contour or edge-level processing is supported by the Gestalt heuristics of proximity, collinearity and closure. Less is known, however, about the developmental trajectory of contour detection and contour integration. Within the physiology of the visual system, long-range horizontal connections in V1 and V2 are the likely candidates for implementing these heuristics. While post-mortem anatomical studies of human infants suggest that horizontal interconnections reach maturity by the second year of life, psychophysical research with infants and children suggests a considerably more protracted development. In the present review, data from infancy to adulthood will be discussed in order to track the development of contour detection and integration. The goal of this review is thus to integrate the development of contour detection and integration with research regarding the development of underlying neural circuitry. We conclude that the ontogeny of this system is best characterized as a developmentally extended period of associative acquisition whereby horizontal connectivity becomes functional over longer and longer distances, thus becoming able to effectively integrate over greater spans of visual space.

  1. A fast contour descriptor algorithm for supernova imageclassification

    Energy Technology Data Exchange (ETDEWEB)

    Aragon, Cecilia R.; Aragon, David Bradburn

    2006-07-16

    We describe a fast contour descriptor algorithm and its application to a distributed supernova detection system (the Nearby Supernova Factory) that processes 600,000 candidate objects in 80 GB of image data per night. Our shape-detection algorithm reduced the number of false positives generated by the supernova search pipeline by 41% while producing no measurable impact on running time. Fourier descriptors are an established method of numerically describing the shapes of object contours, but transform-based techniques are ordinarily avoided in this type of application due to their computational cost. We devised a fast contour descriptor implementation for supernova candidates that meets the tight processing budget of the application. Using the lowest-order descriptors (F{sub 1} and F{sub -1}) and the total variance in the contour, we obtain one feature representing the eccentricity of the object and another denoting its irregularity. Because the number of Fourier terms to be calculated is fixed and small, the algorithm runs in linear time, rather than the O(n log n) time of an FFT. Constraints on object size allow further optimizations so that the total cost of producing the required contour descriptors is about 4n addition/subtraction operations, where n is the length of the contour.

  2. Visual search of illusory contours: Shape and orientation effects

    Directory of Open Access Journals (Sweden)

    Gvozdenović Vasilije

    2008-01-01

    Full Text Available Illusory contours are specific class of visual stimuli that represent stimuli configurations perceived as integral irrespective of the fact that they are given in fragmented uncompleted wholes. Due to their specific features, illusory contours gained much attention in last decade representing prototype of stimuli used in investigations focused on binding problem. On the other side, investigations of illusory contours are related to problem of the level of their visual processing. Neurophysiologic studies show that processing of illusory contours proceed relatively early, on the V2 level, on the other hand most of experimental studies claim that illusory contours are perceived with engagement of visual attention, binding their elements to whole percept. This research is focused on two experiments in which visual search of illusory contours are based on shape and orientation. The main experimental procedure evolved the task proposed by Bravo and Nakayama where instead of detection, subjects were performing identification of one among two possible targets. In the first experiment subjects detected the presence of illusory square or illusory triangle, while in the second experiment subject were detecting two different orientations of illusory triangle. The results are interpreted in terms of visual search and feature integration theory. Beside the type of visual search task, search type proved to be dependent of specific features of illusory shapes which further complicate theoretical interpretation of the level of their perception.

  3. A possible analogy between contours in mathematics--as exemplified by Cauchy's integral formula--and contours in the arts.

    Science.gov (United States)

    Gerr, S

    1982-01-01

    An attempt is made to draw an analogy between contour drawing and a particular mathematical theorem. The analogy is seen to depend on the fact that both methods use definite values along a contour to imply a totality of values within the contour; thus, the use of a part to suggest the whole, by way of a hypothetical 'gestalt-like integration' in the case of the art contour, and the usual process of mathematical integration in the case of Cauchy's formula. Examples illustrating the analogy are drawn from a wide range of artistic work: a modern American drawing, a Cro-Magnon cave painting, and two Chinese works. The traditional Chinese philosophy of painting is invoked in support of the analogy because of its explicit emphasis on the primacy of outline drawing in Chinese painting. Some speculations are offered on further development and application of the analogy.

  4. Contours, Cherokee County Contours, Published in unknown, 1:2400 (1in=200ft) scale, City of Woodstock.

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — This Contours dataset, published at 1:2400 (1in=200ft) scale, was produced all or in part from LIDAR information as of unknown. It is described as 'Cherokee County...

  5. Contours - CONTOURS_24K_USGS_ADRIAN: Elevation Contours from 7.5-Minute Topographic Quadrangle Maps, Grouped into the 30' x 1째 Adrian Quadrangle, Indiana, Michigan, and Ohio (United States Geological Survey, 1:24,000, Line Shapefile)

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — CONTOURS_24K_USGS_ADRIAN is a shapefile containing elevation contours produced at a scale of 1:24,000, grouped into a 30' x 1째 quadrangle block. Elevation values are...

  6. Review of the Mechanisms and Effects of Noninvasive Body Contouring Devices on Cellulite and Subcutaneous Fat.

    Science.gov (United States)

    Alizadeh, Zahra; Halabchi, Farzin; Mazaheri, Reza; Abolhasani, Maryam; Tabesh, Mastaneh

    2016-10-01

    Today, different kinds of non-invasive body contouring modalities, including cryolipolysis, radiofrequency (RF), low-level laser therapy (LLLT), and high-intensity focused ultrasound (HIFU) are available for reducing the volume of subcutaneous adipose tissue or cellulite. Each procedure has distinct mechanisms for stimulating apoptosis or necrosis adipose tissue. In addition to the mentioned techniques, some investigations are underway for analyzing the efficacy of other techniques such as whole body vibration (WBV) and extracorporeal shockwave therapy (ESWT). In the present review the mechanisms, effects and side effects of the mentioned methods have been discussed. The effect of these devices on cellulite or subcutaneous fat reduction has been assessed. We searched pubmed, google scholar and the cochrane databases for systemic reviews, review articles, meta-analysis and randomized clinical trials up to February 2015. The keywords were subcutaneous fat, cellulite, obesity, noninvasive body contouring, cryolipolysis, RF, LLLT, HIFU, ESWT and WBV with full names and abbreviations. We included seven reviews and 66 original articles in the present narrative review. Most of them were applied on normal weight or overweight participants (body mass index cellulite in some body areas. However, the clinical effects are mild to moderate, for example 2 - 4 cm circumference reduction as a sign of subcutaneous fat reduction during total treatment sessions. Overall, there is no definitive noninvasive treatment method for cellulite. Additionally, due to the methodological differences in the existing evidence, comparing the techniques is difficult.

  7. Implementation of RSA 2048-bit and AES 256-bit with Digital Signature for Secure Electronic Health Record Application

    Directory of Open Access Journals (Sweden)

    Mohamad Ali Sadikin

    2016-10-01

    Full Text Available This research addresses the implementation of encryption and digital signature technique for electronic health record to prevent cybercrime such as robbery, modification and unauthorised access. In this research, RSA 2048-bit algorithm, AES 256-bit and SHA 256 will be implemented in Java programming language. Secure Electronic Health Record Information (SEHR application design is intended to combine given services, such as confidentiality, integrity, authentication, and nonrepudiation. Cryptography is used to ensure the file records and electronic documents for detailed information on the medical past, present and future forecasts that have been given only to the intended patients. The document will be encrypted using an encryption algorithm based on NIST Standard. In the application, there are two schemes, namely the protection and verification scheme. This research uses black-box testing and whitebox testing to test the software input, output, and code without testing the process and design that occurs in the system.We demonstrated the implementation of cryptography in SEHR. The implementation of encryption and digital signature in this research can prevent archive thievery.

  8. Brightness/darkness induction and the genesis of a contour.

    Science.gov (United States)

    Roncato, Sergio

    2014-01-01

    Visual contours often result from the integration or interpolation of fragmented edges. The strength of the completion increases when the edges share the same contrast polarity (CP). Here we demonstrate that the appearance in the perceptual field of this integrated unit, or contour of invariant CP, is concomitant with a vivid brightness alteration of the surfaces at its opposite sides. To observe this effect requires some stratagems because the formation in the visual field of a contour of invariant CP normally engenders the formation of a second contour and then the rise of two streams of induction signals that interfere in different ways. Particular configurations have been introduced that allow us to observe the induction effects of one contour taken in isolation. I documented these effects by phenomenological observations and psychophysical measurement of the brightness alteration in relation to luminance contrast. When the edges of the same CP complete to form a contour, the background of homogeneous luminance appears to dim at one side and to brighten at the opposite side (in accord with the CP). The strength of the phenomenon is proportional to the local luminance contrast. This effect weakens or nulls when the contour of the invariant CP separates surfaces filled with different gray shades. These conflicting results stimulate a deeper exploration of the induction phenomena and their role in the computation of brightness contrast. An alternative perspective is offered to account for some brightness illusions and their relation to the phenomenal transparency. The main assumption asserts that, when in the same region induction signals of opposite CP overlap, the filling-in is blocked unless the image is stratified into different layers, one for each signal of the same polarity. Phenomenological observations document this "solution" by the visual system.

  9. Brightness/darkness induction and the genesis of a contour

    Directory of Open Access Journals (Sweden)

    Sergio eRoncato

    2014-10-01

    Full Text Available Visual contours often result from the integration or interpolation of fragmented edges.The strength of the completion increases when the edges share the same contrast polarity (CP. Here we demonstrate that the appearance in the perceptual field of this integrated unit, or contour of invariant CP, is concomitant with a vivid brightness alteration of the surfaces at its opposite sides. To observe this effect requires some stratagems because the formation in the visual field of a contour of invariant CP normally engenders the formation of a second contour and then the rise of two streams of induction signals that interfere in different ways. Particular configurations have been introduced that allow us to observe the induction effects of one contour taken in isolation. I documented these effects by phenomenological observations and psychophysical measurement of the brightness alteration in relation to luminance contrast. When the edges of the same CP complete to form a contour, the background of homogeneous luminance appears to dim at one side and to brighten at the opposite side (in accord with the CP. The strength of the phenomenon is proportional to the local luminance contrast. This effect weakens or nulls when the contour of the invariant CP separates surfaces filled with different grey shades.These conflicting results stimulate a deeper exploration of the induction phenomena and their role in the computation of brightness contrast. An alternative perspective is offered to account for some brightness illusions and their relation to the phenomenal transparency. The main assumption asserts that, when in the same region induction signals of opposite CP overlap, the filling-in are blocked unless the image is stratified into different layers, one for each signal of the same polarity. Phenomenological observations document this solution by the visual system

  10. Development of a contour meter; Desarrollo de un contornimetro

    Energy Technology Data Exchange (ETDEWEB)

    Andrada C, F.A. [Autoridad Regulatoria Nuclear, Av. Libertador 8250, Ciudad Autonoma de Buenos Aires (Argentina); Sanz, D.E. [Fundacion Escuela de Medicina Nuclear, Garibaldi 405, Capital, Mendoza (Argentina)]. e-mail: andrada@argentina.com

    2006-07-01

    The dosimetric calculation in patients that receive radiotherapy treatment it requires the one knowledge of the geometry of some anatomical portions, which differs from a patient to another. Making reference to the specific case of mammary neoplasia, one of the measurements that is carried out on the patient is the acquisition of the contour of the breast, which is determined from a point marked on the breastbone until another point marked on the lateral of the thorax, below the armpit, with the patient located in the irradiation position. This measurement is carried out with the help of a mechanical contour meter that is a device conformed by a series of wires with a polymeric coating, which support on the breast of the patient and it reproduces its form. Then it is transported in the more careful possible form on a paper and the contour is traced with a tracer one. The geometric error associated to this procedure is of {+-}1 cm, which is sensitive of being reduced. The present work finds its motivation in the patient's radiological protection radiotherapy. The maximum error in dose allowed in radiotherapeutic treatments is 5%. It would be increase the precision and with it to optimize the treatment received by the patient, reducing the error in the acquisition process of the mammary contour. With this objective, a digital device is designed whose operation is based in the application of a spatial transformation on a picture of the mammary contour, which corrects the geometric distortion introduced in the process of the photographic acquisition. An algorithm that allows to obtain a front image (without distortion) of the plane of the contour was developed. A software tool especially developed carries out the processing of the digital images. The maximum geometric error detected in the validation process is 2 mm located on a small portion of the contour. (Author)

  11. AN APPROXIMATE EXPRESSION RELATED WITH RSA FIXED POINTS%与RSA不动点有关的一个渐近表示

    Institute of Scientific and Technical Information of China (English)

    于秀源

    2004-01-01

    Let T=T(n,e,α) be the number of fixed points of RSA(n,e) that are co-prime with n=pq,and A,B be sets of prime numbers in (1,x) and (1,y) respectively. An estimation on the mean-valueM(A,B,e,α) = 1(#A)(#B) ∑p∈A,q∈B,(p,q)=1 logT(pq,e,α) is given.

  12. Predicting 3D pose in partially overlapped X-ray images of knee prostheses using model-based Roentgen stereophotogrammetric analysis (RSA).

    Science.gov (United States)

    Hsu, Chi-Pin; Lin, Shang-Chih; Shih, Kao-Shang; Huang, Chang-Hung; Lee, Chian-Her

    2014-12-01

    After total knee replacement, the model-based Roentgen stereophotogrammetric analysis (RSA) technique has been used to monitor the status of prosthetic wear, misalignment, and even failure. However, the overlap of the prosthetic outlines inevitably increases errors in the estimation of prosthetic poses due to the limited amount of available outlines. In the literature, quite a few studies have investigated the problems induced by the overlapped outlines, and manual adjustment is still the mainstream. This study proposes two methods to automate the image processing of overlapped outlines prior to the pose registration of prosthetic models. The outline-separated method defines the intersected points and segments the overlapped outlines. The feature-recognized method uses the point and line features of the remaining outlines to initiate registration. Overlap percentage is defined as the ratio of overlapped to non-overlapped outlines. The simulated images with five overlapping percentages are used to evaluate the robustness and accuracy of the proposed methods. Compared with non-overlapped images, overlapped images reduce the number of outlines available for model-based RSA calculation. The maximum and root mean square errors for a prosthetic outline are 0.35 and 0.04 mm, respectively. The mean translation and rotation errors are 0.11 mm and 0.18°, respectively. The errors of the model-based RSA results are increased when the overlap percentage is beyond about 9%. In conclusion, both outline-separated and feature-recognized methods can be seamlessly integrated to automate the calculation of rough registration. This can significantly increase the clinical practicability of the model-based RSA technique.

  13. Identification of RCN1 and RSA3 as ethanol-tolerant genes in Saccharomyces cerevisiae using a high copy barcoded library.

    Science.gov (United States)

    Anderson, Michael J; Barker, Sarah L; Boone, Charlie; Measday, Vivien

    2012-02-01

    Saccharomyces cerevisiae (S. cerevisiae) encounters a multitude of stresses during industrial processes such as wine fermentation including ethanol toxicity. High levels of ethanol reduce the viability of yeast and may prevent completion of fermentation. The identification of ethanol-tolerant genes is important for creating stress-resistant industrial yeast, and S. cerevisiae genomic resources have been utilized for this purpose. We have employed a molecular barcoded yeast open reading frame (MoBY-ORF) high copy plasmid library to identify ethanol-tolerant genes in both the S. cerevisiae S288C laboratory and M2 wine strains. We find that increased dosage of either RCN1 or RSA3 improves tolerance of S288C and M2 to toxic levels of ethanol. RCN1 is a regulator of calcineurin, whereas RSA3 has a role in ribosome maturation. Additional fitness advantages conferred upon overproduction of RCN1 and RSA3 include increased resistance to cell wall degradation, heat, osmotic and oxidative stress. We find that the M2 wine yeast strain is generally more tolerant of stress than S288C with the exception of translation inhibition, which affects M2 growth more severely than S288C. We conclude that regulation of ribosome biogenesis and ultimately translation is a critical factor for S. cerevisiae survival during industrial-related environmental stress. © 2011 Federation of European Microbiological Societies. Published by Blackwell Publishing Ltd. All rights reserved.

  14. Survey of Layer Flocks Contamination to Mycoplasma gallisepticum in East Azerbaijan Province by Rapid Slide Agglutination (R.S.A Method

    Directory of Open Access Journals (Sweden)

    Mehrdad Nazeri

    2012-01-01

    Full Text Available The objective of this study was to evaluation of R.S.A. method efficiency in distinguishing M. gallisepticum and contamination rate of MG in Iran. In this study totally 300 serum samples from 20 farms collected and sent to laboratory. In lab, samples centrifuged at 2500 rpm for 5 min. Separated serums kept in Bain Marie at 56ºC. Then 50 μ of serum are mixed with 50 : RSA-MG antigen on the slide and were assayed under light. Of 300 serum samples, 52 samples (17.3% were positive, 10 samples (3.3% were suspicious and 238 samples (79.3% were negative reported. Finally, primarily can be conclude that R.S.A method is specific method for detection of M. gallisepticum and has minimum Err with maximum sensitivity. Secondarily can be conclude that contamination rate of M. gallisepticum in Iran is higher than standard levels and must be take measures in this field.

  15. Contours, 2' Contours for Iredell County provided by 2003 NC Floodplain Mapping Program data, Published in 2007, 1:4800 (1in=400ft) scale, Iredell County GIS.

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — This Contours dataset, published at 1:4800 (1in=400ft) scale, was produced all or in part from LIDAR information as of 2007. It is described as '2' Contours for...

  16. Contours, Contour layer with some elevation information for the northern half of the County., Published in 2000, 1:2400 (1in=200ft) scale, Walworth County.

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — This Contours dataset, published at 1:2400 (1in=200ft) scale, was produced all or in part from Orthoimagery information as of 2000. It is described as 'Contour layer...

  17. Contours, Two-foot contours for Oconee County, Georgia, Published in 2006, 1:12000 (1in=1000ft) scale, Northeast Georgia Regional Commission.

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — This Contours dataset, published at 1:12000 (1in=1000ft) scale, was produced all or in part from LIDAR information as of 2006. It is described as 'Two-foot contours...

  18. Contours, Two-foot contours for Athens-Clarke County, Georgia, Published in 2005, 1:12000 (1in=1000ft) scale, Northeast Georgia Regional Commission.

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — This Contours dataset, published at 1:12000 (1in=1000ft) scale, was produced all or in part from LIDAR information as of 2005. It is described as 'Two-foot contours...

  19. Review of the Mechanisms and Effects of Noninvasive Body Contouring Devices on Cellulite and Subcutaneous Fat

    Directory of Open Access Journals (Sweden)

    Alizadeh

    2016-07-01

    Full Text Available Context Today, different kinds of non-invasive body contouring modalities, including cryolipolysis, radiofrequency (RF, low-level laser therapy (LLLT, and high-intensity focused ultrasound (HIFU are available for reducing the volume of subcutaneous adipose tissue or cellulite. Each procedure has distinct mechanisms for stimulating apoptosis or necrosis adipose tissue. In addition to the mentioned techniques, some investigations are underway for analyzing the efficacy of other techniques such as whole body vibration (WBV and extracorporeal shockwave therapy (ESWT. In the present review the mechanisms, effects and side effects of the mentioned methods have been discussed. The effect of these devices on cellulite or subcutaneous fat reduction has been assessed. Evidence Acquisition We searched pubmed, google scholar and the cochrane databases for systemic reviews, review articles, meta-analysis and randomized clinical trials up to February 2015. The keywords were subcutaneous fat, cellulite, obesity, noninvasive body contouring, cryolipolysis, RF, LLLT, HIFU, ESWT and WBV with full names and abbreviations. Results We included seven reviews and 66 original articles in the present narrative review. Most of them were applied on normal weight or overweight participants (body mass index < 30 kg/m2 in both genders with broad range of ages (18 to 50 years on average. In the original articles, the numbers of included methods were: 10 HIFU, 13 RF, 22 cryolipolysis, 11 LLLT, 5 ESWT and 4 WBV therapies. Six of the articles evaluated combination therapies and seven compared the effects of different devices. Conclusions Some of the noninvasive body contouring devices in animal and human studies such as cryolipolysis, RF, LLLT and HIFU showed statistical significant effects on body contouring, removing unwanted fat and cellulite in some body areas. However, the clinical effects are mild to moderate, for example 2 - 4 cm circumference reduction as a sign of

  20. Medical Image Segmentation through Bat-Active Contour Algorithm

    Directory of Open Access Journals (Sweden)

    Rabiu O. Isah

    2017-01-01

    Full Text Available In this research work, an improved active contour method called Bat-Active Contour Method (BAACM using bat algorithm has been developed. The bat algorithm is incorporated in order to escape local minima entrapped into by the classical active contour method, stabilize contour (snake movement and accurately, reach boundary concavity. Then, the developed Bat-Active Contour Method was applied to a dataset of medical images of the human heart, bone of knee and vertebra which were obtained from Auckland MRI Research Group (Cardiac Atlas Website, University of Auckland. Set of similarity metrics, including Jaccard index and Dice similarity measures were adopted to evaluate the performance of the developed algorithm. Jaccard index values of 0.9310, 0.9234 and 0.8947 and Dice similarity values of 0.8341, 0.8616 and 0.9138 were obtained from the human heart, vertebra and bone of knee images respectively. The results obtained show high similarity measures between BA-ACM algorithm and expert segmented images. Moreso, traditional ACM produced Jaccard index values 0.5873, 0.5601, 0.6009 and Dice similarity values of 0.5974, 0.6079, 0.6102 in the human heart, vertebra and bone of knee images respectively. The results obtained for traditional ACM show low similarity measures between it and expertly segmented images. It is evident from the results obtained that the developed algorithm performed better compared to the traditional ACM

  1. Parallel peak pruning for scalable SMP contour tree computation

    Energy Technology Data Exchange (ETDEWEB)

    Carr, Hamish A. [Univ. of Leeds (United Kingdom); Weber, Gunther H. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Univ. of California, Davis, CA (United States); Sewell, Christopher M. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Ahrens, James P. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2017-03-09

    As data sets grow to exascale, automated data analysis and visualisation are increasingly important, to intermediate human understanding and to reduce demands on disk storage via in situ analysis. Trends in architecture of high performance computing systems necessitate analysis algorithms to make effective use of combinations of massively multicore and distributed systems. One of the principal analytic tools is the contour tree, which analyses relationships between contours to identify features of more than local importance. Unfortunately, the predominant algorithms for computing the contour tree are explicitly serial, and founded on serial metaphors, which has limited the scalability of this form of analysis. While there is some work on distributed contour tree computation, and separately on hybrid GPU-CPU computation, there is no efficient algorithm with strong formal guarantees on performance allied with fast practical performance. Here in this paper, we report the first shared SMP algorithm for fully parallel contour tree computation, withfor-mal guarantees of O(lgnlgt) parallel steps and O(n lgn) work, and implementations with up to 10x parallel speed up in OpenMP and up to 50x speed up in NVIDIA Thrust.

  2. Active contour model based on force field analysis

    Institute of Scientific and Technical Information of China (English)

    HOU Zhi-qiang; HAN Chong-zhao

    2006-01-01

    The traditional snake initial contour should be close to the true boundary of an object of interest in an image;otherwise,an incorrect result will be obtained.Next,active contours have difficulties progressing into boundary concavities.Moreover,the traditional snake as well as almost all of its improved methods can be easily obtained from the local minimum because snake models are nonconvex.An active contour model based on force field analysis (FFA),namely,FFA snake model,is presented in this paper.Based on analyzing force distribution rules of the distance potential force field,a standard is introduced here to distinguish the false one from contour points.The result is not considered as the final solution when the snake energy is minimal.Furthermore,estimation and calculation should be made according to the established standard;only then can the result be considered final.Thus,the snake is prevented from running into the local minimum.The simulation results show that the FFA snake model has a large capture range and can move a snake into the boundary concavities,and that it is able to obtain the object of interest's contour precisely.Compared with the gradient vector flow snake,this new model has a low computational cost.

  3. After massive weight loss: patients' expectations of body contouring surgery.

    Science.gov (United States)

    Kitzinger, Hugo B; Abayev, Sara; Pittermann, Anna; Karle, Birgit; Bohdjalian, Arthur; Langer, Felix B; Prager, Gerhard; Frey, Manfred

    2012-04-01

    Massive weight loss following bariatric surgery leads to excess skin with functional and aesthetic impairments. Surplus skin can then contribute to problems with additional weight loss or gain. The aims of the current study were to evaluate the frequency of massive soft tissue development in gastric bypass patients, to determine whether males and females experience similar post-bypass body changes, and to learn about the expectations and impairments related to body contouring surgery. A questionnaire addressing information on the satisfaction of body image, quality of life, and expectation of body contouring surgery following massive weight loss was mailed to 425 patients who had undergone gastric bypass surgery between 2003 and 2009. Of these 425 individuals, 252 (59%) patients completed the survey. Ninety percent of women and 88% of men surveyed rated their appearance following massive weight loss as satisfactory, good, or very good. However, 96% of all patients developed surplus skin, which caused intertriginous dermatitis and itching. In addition, patients reported problems with physical activity (playing sports) and finding clothing that fit appropriately. Moreover, 75% of female and 68% of male patients reported desiring body contouring surgery. The most important expectation of body contouring surgery was improved appearance, followed by improved self-confidence and quality of life. Surplus skin resulting from gastric bypass surgery is a common issue that causes functional and aesthetic impairments in patients. Consequently, this increases the desire for body contouring surgery with high expectations for the aesthetic outcome as well as improved life satisfaction.

  4. Incorporating Stream Features into Groundwater Contouring Tools Within GIS.

    Science.gov (United States)

    Bannister, Roger; Kennelly, Patrick

    2016-03-01

    Hydrogeologists often are called upon to estimate surfaces from discrete, sparse data points. This estimation is often accomplished by manually drawing contours on maps using interpolation methods between points of known value while accounting for features known to influence the water table's surface. By contrast, geographic information systems (GIS) are good at creating smooth continuous surfaces from limited data points and allowing the user to represent the resulting surface resulting with contours, but these automated methods often fail to meet the expectations of many hydrogeologists because they do not include knowledge of other influences on the water table. In this study, we seek to fill this gap in the GIS-based methodology for hydrogeologists through an interactive tool that shapes an interpolated surface based on additional knowledge of the water table inferred from gaining or losing streams. The modified surface is reflected in water table contours that, for example, "V" upstream for gaining streams, and can be interactively adjusted to fit the user's expectations. By modifying not only the contours but also the associated interpolated surface, additional contours will follow the same trend, and the modified surface can be used for other analyses like calculating average gradients and flow paths. The tool leverages Esri's ArcGIS Desktop software, building upon a robust suite of mapping tools. We see this as a prototype for other tools that could be developed for hydrogeologists to account for variations in the water table inferred from local topographic trends, pumping or injection wells, and other hydrogeologic features.

  5. Image automatic mosaics based on contour phase correlation

    Institute of Scientific and Technical Information of China (English)

    ZHANG Jing; HU Zhiping; LIU Zhitai; OU Zongying

    2007-01-01

    The image planar mosaics is studied,and an image automatic mosaics algorithm on the basis of contour phase correlation is proposed in this paper.To begin with,by taking into account mere translations and rotations between images,a contour phase correlation algorithm is used to realize the preliminary alignments of images,and the initial projective transformation matrices are obtained.Then,an optimization algorithm is used to optimize the initial projective transformation matrices,and complete the precise image mosaics.The contour phase correlation is an improvement on the conventional phase correlation in two aspects:First,the contours of images are extracted,and the phase correlation is applied to the contours of images instead of the whole original images;Second,when there are multiple peak values approximate to the maximum peak value in the δ function array,their corresponding translations can be regarded as candidate translations and calculated separately,and the best translation can be determined by the optimization of conformability of two images in the overlapping area.The running results show that the proposed algorithm can consistently yield high-quality mosaics,even in the cases of poor or differential lighting conditions,existences of minor rotations,and other complicated displacements between images.

  6. 大规模ad hoc网络下的高效的主动RSA方案%An efficient proactive RSA scheme for large-scale ad hoc networks

    Institute of Scientific and Technical Information of China (English)

    张瑞山; 陈克非

    2007-01-01

    A previous proactive RSA scheme for large-scale ad hoc network has been shown to be faulty. In this paper, we present a new proactive RSA scheme for ad hoc networks, which includes four protocols: the initial key distribution protocol,the share refreshing protocol, the share distribution protocol, and the signature generation protocol. This scheme has two advantages: the building blocks are secure, and the system is efficient.

  7. 新月柄杆菌RsaA分泌系统用于大肠杆菌胞外递送重组蛋白的初步研究%Preliminary Study on Exportation of Heterologous Recombinant Proteins in Escherichia coli Utilizing RsaA Secretion System of Caulobacter crescentus

    Institute of Scientific and Technical Information of China (English)

    宁亚蕾; 周立雄; 肖斌; 张卫军; 曾浩; 毛旭虎; 邹全明

    2008-01-01

    目的:构建基于新月柄杆菌RsaA外运机制的以大肠杆菌为宿主的原核胞外分泌表达载体系统.方法:利用分子克隆手段,按RsaA分泌系统操纵子组织方式,将RsaA系统外运功能基因配合以异源调控序列克隆至pQE30骨架质粒.以绿色荧光蛋白(GFP)为报告分子、大肠杆菌M15为宿主菌,诱导表达后通过Western Blotting检测培养上清中GFP的表达.结果:获得了与设计完全一致的pQABPS载体,利用该载体系统,在培养上清中报告分子GFP的表达明显增加,且是通过特异的RsaA外运机制被分泌至胞外的,而非渗漏表达或简单的信号肽引导.结论:在大肠杆菌中重现了RsaA分泌系统的外运功能,为该系统在基因工程领域的应用研究打下了良好基础.

  8. Long-term quality-of-life improvement in gastric banding patients from body-contouring surgery.

    Science.gov (United States)

    Lanthaler, Monika; Mattesich, Monika; Nehoda, Hermann; Puelzl, Petra; Matiasek, Johannes; Nitto, Agnese; Pierer, Gerhard; Kinzl, Johann

    2015-01-01

    Following my prior study of long-term results after laparoscopic gastric banding concerning operative outcome and complications involving the gastric band itself, I now focus on long-term quality-of-life improvement in the same study group after body-contouring surgery. As determined from our electronic patient data system, 72 patients from the former study group subsequently sought body-contouring surgery at our hospital after successful weight loss. Patients were enrolled in a telephone interview and asked about their expectations and body image before and after postbariatric aesthetic surgery and how it altered their well-being in addition to the weight loss achieved with the gastric band. All patients undergoing postbariatric aesthetic surgery felt extremely uneasy with the hanging skin resulting from weight reduction. Patients cannot imagine the degree of dissatisfaction they will experience from the sagging skin that comes with weight loss. Hardly any patient expected fewer scars than he ultimately had after body-contouring surgery and reported an extreme improvement in body image. Gastric banding should not be performed without informing patients about the need for postbariatric body-contouring surgery, because most patients not forewarned suffer greatly from their body image after weight loss.

  9. Functional PstI/RsaI polymorphism in CYP2E1 is associated with the development, progression and poor outcome of gastric cancer.

    Directory of Open Access Journals (Sweden)

    Jin Feng

    Full Text Available BACKGROUND: Cytochrome P450 2E1 (CYP2E1, an ethanol-inducible enzyme, has been shown to metabolically activate various carcinogens, which is critical for the development and progression of cancers. It has demonstrated that CYP2E1 polymorphisms alter the transcriptional activity of the gene. However, studies on the association between CYP2E1 polymorphisms (PstI/RsaI or DraI and gastric cancer have reported conflicting results. Thus, the aim of the present study was to investigate whether CYP2E1 polymorphisms is associated with the development and progression of gastric cancer and its prognosis in Chinese patients. METHODS: A case-control study was conducted in which CYP2E1 PstI/RsaI and DraI polymorphisms were analyzed in 510 Chinese patients with gastric cancer and 510 age- and sex- matched healthy controls by PCR-RFLP. Odds ratios were estimated by multivariate logistic regression, and the lifetime was calculated by Kaplan-Meier survival curves. In addition, a meta-analysis was also conducted to verify the findings. RESULTS: For CYP2E1 PstI/RsaI polymorphism, C2C2 homozygotes (OR = 2.15; CI: 1.18-3.94 and C2 carriers (OR = 1.48; CI: 1.13-1.96 were associated with an increased risk of gastric cancer when compared with C1C1 homozygotes. Both C1C2 and C2C2 genotypes were associated with advanced stage, but not the grade of gastric cancer. Moreover, C2C2 genotype was identified as an independent marker of poor overall survival for gastric cancer. However, there was not any significant association between CYP2E1 DraI polymorphism and the risk of gastric cancer. In the meta-analysis, pooled data from 13 studies confirmed that the CYP2E1 PstI/RsaI polymorphism was associated with a significantly increased risk of gastric cancer. CONCLUSION: CYP2E1 PstI/RsaI polymorphism is associated with increased risk of development, progression and poor prognosis of gastric cancer in Chinese patients. Pooled data from 13 studies, mainly in Asian countries, are in

  10. Layering-based Breakpoint Handling in Contour Line Extraction

    Institute of Scientific and Technical Information of China (English)

    CHEN Dan; LONG Yi; CAI Jinhua

    2003-01-01

    This paper deals withthe automatic connection of contourlines extracted from a scanned browngeographical map. For the variety oftopographical elements contained on amap, the factors causing the interrup-tion of contour line are also multiform,which make the connection task verydifficult. On the basis of separatingthose elements always making the con-tours break and regarding them as ref-erent layers, a layering-based methodis presented. The purpose is to takeinto account property information (likeinclination and configuration) of con-tour lines when they come across otherdifferent symbols, such as gully, cliff,dry land and elevation annotation etc.In this paper, the authors propose thatit should be far more effective and di-rect to adopt different algorithmic op-erators to different factors than usingsingle one operator to all.

  11. A Robust Algorithm of Contour Extraction for Vehicle Tracking

    Institute of Scientific and Technical Information of China (English)

    FANZhimin; ZHOUJie; GAODashan

    2003-01-01

    Contour extraction of moving vehicle is an important and challenging issue in traffic surveillance. In this paper, a robust algorithm is proposed for contour ex-traction and moving vehicle tracking. First, we establish a modified snake model and utilize the directional infor-mation of the edge map to guide the snaxels' behavior.Then an adaptive shape restriction is embedded into the algorithm to govern the scope of the snake's motion, and Kalman filter is employed to estimate spatio-temporal rela-tionship between successive frames. In addition~ multiple refinements are suggested to compensate for the snake's vulnerability to fake edges. All of them contribute to a ro-bust overall performance in contour extraction and vehicle tracking. Experimental results in real traffic scene prove the effectiveness of our algorithm.The comparison with conventional snakes is also provided.

  12. The perception of 3D shape from planar cut contours.

    Science.gov (United States)

    Egan, Eric J L; Todd, James T; Phillips, Flip

    2011-10-01

    A new computational analysis is described for estimating 3D shapes from orthographic images of surfaces that are textured with planar cut contours. For any given contour pattern, this model provides a family of possible interpretations that are all related by affine scaling and shearing transformations in depth, depending on the specific values of its free parameters that are used to compute the shape estimate. Two psychophysical experiments were performed in an effort to compare the model predictions with observers' judgments of 3D shape for developable and non-developable surfaces. The results reveal that observers' perceptions can be systematically distorted by affine scaling and shearing transformations in depth and that the magnitude and direction of these distortions vary systematically with the 3D orientations of the contour planes.

  13. The TICTOP nozzle: a new nozzle contouring concept

    Science.gov (United States)

    Frey, Manuel; Makowka, Konrad; Aichner, Thomas

    2016-10-01

    Currently, mainly two types of nozzle contouring methods are applied in space propulsion: the truncated ideal contour (TIC) and the thrust-optimized parabola (TOP). This article presents a new nozzle contouring method called TICTOP, combining elements of TIC and TOP design. The resulting nozzle is shock-free as the TIC and therefore does not induce restricted shock separation leading to excessive side-loads. Simultaneously, the TICTOP nozzle will allow higher nozzle wall exit pressures and hence give a better separation margin than is the case for a TIC. Hence, this new nozzle type combines the good properties of TIC and TOP nozzles and eliminates their drawbacks. It is especially suited for first stage application in launchers where flow separation and side-loads are design drivers.

  14. Scattering Suppression and Absorption Enhancement in Contour Nanoantennas

    CERN Document Server

    Onal, E Doruk

    2015-01-01

    The expanding application spectrum of plasmonic nanoantennas demand versatile design approaches to tailor the antenna properties for specific requirements. The design efforts primarily concentrate on shifting the operation wavelength or enhancing the local fields by manipulating the size and shape of the nanoantenna. Here, we propose a design path to control the absorption and scattering characteristics of a dipole nanoantenna by introducing a hollow region inside the nanostructure. The resulting contour geometry can significantly suppress the scattering of the dipole nanoantenna and enhance its absorption simultaneously. Both the dipole and the contour dipole nanoantenna couple to equivalent amount of the incident radiation. The dipole nanoantenna scatters 84% of the coupled power (absorbs the remaining 16%) whereas the contour dipole structure scatters only 28% of the coupled power (absorbs the remaining 72%). This constitutes the transformation from scatter to absorber nanoantenna. The scattering of a cont...

  15. Automatic segmentation of leg bones by using active contours.

    Science.gov (United States)

    Kim, Sunhee; Kim, Youngjun; Park, Sehyung; Lee, Deukhee

    2014-01-01

    In this paper, we present a new active contours model to segment human leg bones in computed tomography images that is based on a variable-weighted combination of local and global intensity. This model can split an object surrounded by both weak and strong boundaries, and also distinguish very adjacent objects with those boundaries. The ability of this model is required for segmentation in medical images, e.g., human leg bones, which are usually composed of highly inhomogeneous objects and where the distances among organs are very close. We developed an evolution equation of a level set function whose zero level set represents a contour. An initial contour is automatically obtained by applying a histogram based multiphase segmentation method. We experimented with computed tomography images from three patients, and demonstrate the efficiency of the proposed method in experimental results.

  16. The ppuI-rsaL-ppuR quorum-sensing system regulates cellular motility, pectate lyase activity, and virulence in potato opportunistic pathogen Pseudomonas sp. StFLB209.

    Science.gov (United States)

    Kato, Taro; Morohoshi, Tomohiro; Someya, Nobutaka; Ikeda, Tsukasa

    2015-01-01

    Pseudomonas sp. StFLB209 was isolated from potato leaf as an N-acylhomoserine lactone (AHL)-producing bacterium and showed a close phylogenetic relationship with P. cichorii, a known plant pathogen. Although there are no reports of potato disease caused by pseudomonads in Japan, StFLB209 was pathogenic to potato leaf. In this study, we reveal the complete genome sequence of StFLB209, and show that the strain possesses a ppuI-rsaL-ppuR quorum-sensing system, the sequence of which shares a high similarity with that of Pseudomonas putida. Disruption of ppuI results in a loss of AHL production as well as remarkable reduction in motility. StFLB209 possesses strong pectate lyase activity and causes maceration on potato tuber and leaf, which was slightly reduced in the ppuI mutant. These results suggest that the quorum-sensing system is well conserved between StFLB209 and P. putida and that the system is essential for motility, full pectate lyase activity, and virulence in StFLB209.

  17. Contour extraction of echocardiographic images based on pre-processing

    Energy Technology Data Exchange (ETDEWEB)

    Hussein, Zinah Rajab; Rahmat, Rahmita Wirza; Abdullah, Lili Nurliyana [Department of Multimedia, Faculty of Computer Science and Information Technology, Department of Computer and Communication Systems Engineering, Faculty of Engineering University Putra Malaysia 43400 Serdang, Selangor (Malaysia); Zamrin, D M [Department of Surgery, Faculty of Medicine, National University of Malaysia, 56000 Cheras, Kuala Lumpur (Malaysia); Saripan, M Iqbal

    2011-02-15

    In this work we present a technique to extract the heart contours from noisy echocardiograph images. Our technique is based on improving the image before applying contours detection to reduce heavy noise and get better image quality. To perform that, we combine many pre-processing techniques (filtering, morphological operations, and contrast adjustment) to avoid unclear edges and enhance low contrast of echocardiograph images, after implementing these techniques we can get legible detection for heart boundaries and valves movement by traditional edge detection methods.

  18. Complications following body contouring surgery after massive weight loss

    DEFF Research Database (Denmark)

    Hasanbegovic, Emir; Sørensen, Jens Ahm

    2014-01-01

    Bariatric surgery is a way to achieve lasting weight loss in the obese. Body contouring surgery seeks to alleviate some of the discomfort caused by the excessive loose skin following massive weight loss. Higher complication rates are described in this type of surgery when done post......-bariatric. The purpose of this article is to compare complication rates of body contouring surgery when performed on patients with weight loss due to bariatric surgery compared to patients who lost weight due to dietary changes and/or exercise....

  19. Wilson loops at strong coupling for curved contours with cusps

    CERN Document Server

    Dorn, Harald

    2015-01-01

    We construct the minimal surface in AdS, relevant for the strong coupling behaviour of local supersymmetric Wilson loops in N=4 SYM for a closed contour formed out of segments of two intersecting circles. Its regularised area is calculated including all divergent parts and the finite renormalised term. Furthermore we prove, that for generic planar curved contours with cusps the cusp anomalous dimensions are functions of the respective cusp angles alone. They do not depend on other local data of the cusps.

  20. Motion estimation of elastic articulated objects from image contours

    Institute of Scientific and Technical Information of China (English)

    PAN Hai-lang; DAI Yue-wei; SHI Lei

    2008-01-01

    A new method of elastic articulated objects (human bodies) modeling was presented based on a new conic curve. The model includes 3D object deform able curves which can represent the deformation of human occluding contours. The deformation of human occluding contour can be represented by adjusting only four de-formation parameters for each limb. Then, the 3D deformation parameters are determined by corresponding 2Dcontours from a sequence of stereo images. The algorithm presented in this paper includes deform able conic curve parameters determination and the plane, 3D conic curve lying on, parameter determination.

  1. McCON - A General Contouring Program for Personal Computers.

    Science.gov (United States)

    1992-09-01

    contourable values in the vicinity of the given data sets. The recent advent of high quality graphics capabilities on personal computers and workstations... quality than screen plots. Contouring Nonconvex Areas By Composite Fragments 29. The triangle mesh generation criteria will always result in the data...7 RC.N.OL3N.O 7704 CON IN~i 7705 COL4=COLOR B2 IFFIFNME.EO’ M’ G’O 10 7777 ý ý9ýFILE=FNME,STATU$:’OLD’ ,ERR=567’i 567 INDOO 568 C ONTI NUý R AD 9,1

  2. [Development of a Software for Automatically Generated Contours in Eclipse TPS].

    Science.gov (United States)

    Xie, Zhao; Hu, Jinyou; Zou, Lian; Zhang, Weisha; Zou, Yuxin; Luo, Kelin; Liu, Xiangxiang; Yu, Luxin

    2015-03-01

    The automatic generation of planning targets and auxiliary contours have achieved in Eclipse TPS 11.0. The scripting language autohotkey was used to develop a software for automatically generated contours in Eclipse TPS. This software is named Contour Auto Margin (CAM), which is composed of operational functions of contours, script generated visualization and script file operations. RESULTS Ten cases in different cancers have separately selected, in Eclipse TPS 11.0 scripts generated by the software could not only automatically generate contours but also do contour post-processing. For different cancers, there was no difference between automatically generated contours and manually created contours. The CAM is a user-friendly and powerful software, and can automatically generated contours fast in Eclipse TPS 11.0. With the help of CAM, it greatly save plan preparation time and improve working efficiency of radiation therapy physicists.

  3. Theory on the molecular characteristic contour(Ⅰ)——A new approach to defining molecular characteristic contour

    Institute of Scientific and Technical Information of China (English)

    赵东霞; 杨忠志

    1999-01-01

    Based on the classical turning point of electron movement in a molecule, a model for defining the molecular characteristic boundary contour is advanced. By using an accurate ab initio MELD program and an auxiliary program, some electron parameters in a molecule, such as the potential felt by an electron, have been evaluated. According to our model and definition, the molecular characteristic contour of the equilibrium geometry configuration is drawn and a vivid intuitive picture for describing the forming or breaking of a chemical bond is displayed.

  4. Organization of contour from motion processing in primate visual cortex

    NARCIS (Netherlands)

    Lamme, V.A.F.; van Dijk, B.W.; Spekreijse, H.

    1994-01-01

    Investigated where contour from motion processing occurs by recording visual evoked potential (VEP) to a stimulus designed to signal the presence of relative motion-sensitive mechanisms. Two human Ss and 3 monkeys participated in the study and had VEP measured on the scalp and intracortically, respe

  5. Pulse contour-derived cardiac output in hemodialysis patients

    DEFF Research Database (Denmark)

    Cordtz, Joakim; Ladefoged, Soeren D

    2010-01-01

    Reliable methods for cardiac output determination are essential for studying the pathophysiology of intradialytic hypotension. Use of the current gold standard, the Transonic monitor, requires an arteriovenous fistula. We wished to verify the accuracy of a method based on finger pulse contour...

  6. Design of a Vibrotactile Vest for Contour Perception

    Directory of Open Access Journals (Sweden)

    Juan Wu

    2012-11-01

    Full Text Available A vibrotactile array is a promising human computer interface which could display graphical information to users in a tactile form. This paper presents the design and testing of an image contour display system with a vibrotactile array. The tactile image display system is attached to the back of the user. It converts visual graphics into 2D tactile images and allows subjects to feel the contours of objects through vibration stimulus. The system consists of a USB camera, 48 (6×8 vibrating motors and an embedded control system. The image is captured by the camera and the 2D contour is extracted and transformed into vibrotactile stimuli using a temporal-spatial dynamic coding method. Preliminary experiments were carried out and the optimal parameters of the vibrating time and duration were explored. To evaluate the feasibility and robustness of this vibration mode, letters were also tactilely displayed and the recognition rate about the alphabet letter display was investigated. It was shown that under the condition of no pre-training for the subjects, the recognition rate was 82%. Such a recognition rate is higher than that of the scanning mode (47.5% and the improved handwriting mode (76.8%. The results indicated that the proposed method was efficient in conveying the contour information to the visually impaired by means of vibrations.

  7. DEVELOPMENT OF VISUALLY GUIDED BEHAVIOR REQUIRES ORIENTED CONTOURS

    NARCIS (Netherlands)

    BRENNER, E; CORNELISSEN, FW

    1992-01-01

    Kittens do not learn to use visual information to guide their behaviour if they are deprived of the optic flow that accompanies their own movements. We show that the optic flow that is required for developing visually guided behaviour is derived from changes in contour orientations, rather than from

  8. Large-scale Optimization of Contoured Beam Reflectors and Reflectarrays

    DEFF Research Database (Denmark)

    Borries, Oscar; Sørensen, Stig B.; Jørgensen, Erik;

    2016-01-01

    Designing a contoured beam reflector or performing a direct optimization of a reflectarray requires a mathematical optimization procedure to determine the optimum design of the antenna. A popular approach, used in the market-leading TICRA software POS, can result in computation times on the order...

  9. Design of a Vibrotactile Vest for Contour Perception

    Directory of Open Access Journals (Sweden)

    Juan Wu

    2012-11-01

    Full Text Available A vibrotactile array is a promising human computer interface which could display graphical information to users in a tactile form. This paper presents the design and testing of an image contour display system with a vibrotactile array. The tactile image display system is attached to the back of the user. It converts visual graphics into 2D tactile images and allows subjects to feel the contours of objects through vibration stimulus. The system consists of a USB camera, 48 (6×8 vibrating motors and an embedded control system. The image is captured by the camera and the 2D contour is extracted and transformed into vibrotactile stimuli using a temporal‐spatial dynamic coding method. Preliminary experiments were carried out and the optimal parameters of the vibrating time and duration were explored. To evaluate the feasibility and robustness of this vibration mode, letters were also tactilely displayed and the recognition rate about the alphabet letter display was investigated. It was shown that under the condition of no pre‐training for the subjects, the recognition rate was 82%. Such a recognition rate is higher than that of the scanning mode (47.5% and the improved handwriting mode (76.8%. The results indicated that the proposed method was efficient in conveying the contour information to the visually impaired by means of vibrations.

  10. Surface Perception from Local Analysis of Texture and Contour.

    Science.gov (United States)

    1980-02-01

    Gibson, 1971; Kennedy, 19741 or a learned skill of interpretation analogous to reading, subject to cultural convention (e.g., [ Arnheim , 19541...contours, highlights, and shading edges tell us of the local Gaussian curvature in some cases. 4 t . SStevens I102 References REFERENCES Arnheim . R

  11. Use of rapidly hardening hydroxyapatite cement for facial contouring surgery.

    Science.gov (United States)

    Lee, Dong Won; Kim, Ji Ye; Lew, Dae Hyun

    2010-07-01

    Hydroxyapatite cement is an ideal alloplastic material to replace the autogenous bone grafts in craniofacial surgery. Hydroxyapatite cement is advantageous because it can be easily molded by hand unlike other alloplastic materials such as silicone and high-density polyethylene. For aesthetic applications of hydroxyapatite cement, we evaluated the efficacy and safety of the rapidly hardening hydroxyapatite cement used in facial contour augmentation, especially for the forehead and the malar area. A total of 18 cases of facial skeleton augmentation or contouring surgery using rapidly hardening hydroxyapatite cement (Mimix; Biomet, Warsaw, IN) were examined, and the long-term cosmetic results and any complications were also analyzed. The aims of facial contouring surgeries were to correct the following conditions: hemifacial microsomia, craniosynostosis, posttraumatic facial deformity, deformity after tumor resection, dentofacial deformity, and Romberg disease. The application sites of hydroxyapatite cement were the forehead, malar area, chin, and paranasal area. A mean of 16 g (range, 5-50 g) of the hydroxyapatite cement was used. Postoperative infection, seroma, and migration of the implant were not observed during the follow-up period of 23 months. Rapidly hardening hydroxyapatite cement, Mimix, is easy to manipulate, promptly sclerotized, and can be replaced by living bone tissue, with a low complication rate. Therefore, it can be an optimal treatment that can be used instead of other conventional types of alloplastic materials used in facial contouring surgery.

  12. Automatic Image Segmentation Using Active Contours with Univariate Marginal Distribution

    Directory of Open Access Journals (Sweden)

    I. Cruz-Aceves

    2013-01-01

    Full Text Available This paper presents a novel automatic image segmentation method based on the theory of active contour models and estimation of distribution algorithms. The proposed method uses the univariate marginal distribution model to infer statistical dependencies between the control points on different active contours. These contours have been generated through an alignment process of reference shape priors, in order to increase the exploration and exploitation capabilities regarding different interactive segmentation techniques. This proposed method is applied in the segmentation of the hollow core in microscopic images of photonic crystal fibers and it is also used to segment the human heart and ventricular areas from datasets of computed tomography and magnetic resonance images, respectively. Moreover, to evaluate the performance of the medical image segmentations compared to regions outlined by experts, a set of similarity measures has been adopted. The experimental results suggest that the proposed image segmentation method outperforms the traditional active contour model and the interactive Tseng method in terms of segmentation accuracy and stability.

  13. Integrability and Wilson loops: the wavy line contour

    CERN Document Server

    Cagnazzo, A

    2013-01-01

    The Wilson loop with a wavy line contour is studied using integrable methods. The auxiliary problem is solved and the Lax operator is built to first order in perturbation theory, considering a small perturbation from the straight line. Finally the spectral curve of the solution is considered.

  14. The role of non-CRF inhibition in contour detection

    NARCIS (Netherlands)

    Grigorescu, Cosmin; Petkov, Nicolai; Westenberg, Michel A.; Skala,

    2003-01-01

    We propose a biologically motivated computational step, called non-classical receptive field (non-CRF) inhibition, to improve the performance of contour detectors. Non-CRF inhibition is exhibited by 80% of the orientation selective neurons in the primary visual cortex of macaque monkeys and has been

  15. Active contours for localizing polyps in colonoscopic NBI image data

    Science.gov (United States)

    Breier, Matthias; Gross, Sebastian; Behrens, Alexander; Stehle, Thomas; Aach, Til

    2011-03-01

    Colon cancer is the third most common type of cancer in the United States of America. Every year about 140,000 people are newly diagnosed with colon cancer. Early detection is crucial for a successful therapy. The standard screening procedure is called colonoscopy. Using this endoscopic examination physicians can find colon polyps and remove them if necessary. Adenomatous colon polyps are deemed a preliminary stage of colon cancer. The removal of a polyp, though, can lead to complications like severe bleedings or colon perforation. Thus, only polyps diagnosed as adenomatous should be removed. To decide whether a polyp is adenomatous the polyp's surface structure including vascular patterns has to be inspected. Narrow-Band imaging (NBI) is a new tool to improve visibility of vascular patterns of the polyps. The first step for an automatic polyp classification system is the localization of the polyp. We investigate active contours for the localization of colon polyps in NBI image data. The shape of polyps, though roughly approximated by an elliptic form, is highly variable. Active contours offer the flexibility to adapt to polyp variation well. To avoid clustering of contour polygon points we propose the application of active rays. The quality of the results was evaluated based on manually segmented polyps as ground truth data. The results were compared to a template matching approach and to the Generalized Hough Transform. Active contours are superior to the Hough transform and perform equally well as the template matching approach.

  16. Luminance contours can gate afterimage colors and 'real' colors

    NARCIS (Netherlands)

    Anstis, S.; Vergeer, M.L.T.; Lier, R.J. van

    2012-01-01

    It has long been known that colored images may elicit afterimages in complementary colors. We have already shown (Van Lier, Vergeer, & Anstis, 2009) that one and the same adapting image may result in different afterimage colors, depending on the test contours presented after the colored image. The c

  17. A contoured continuum surface force model for particle methods

    Science.gov (United States)

    Duan, Guangtao; Koshizuka, Seiichi; Chen, Bin

    2015-10-01

    A surface tension model is essential to simulate multiphase flows with deformed interfaces. This study develops a contoured continuum surface force (CCSF) model for particle methods. A color function that varies sharply across the interface to mark different fluid phases is smoothed in the transition region, where the local contour curvature can be regarded as the interface curvature. The local contour passing through each reference particle in the transition region is extracted from the local profile of the smoothed color function. The local contour curvature is calculated based on the Taylor series expansion of the smoothed color function, whose derivatives are calculated accurately according to the definition of the smoothed color function. Two schemes are proposed to specify the smooth radius: fixed scheme, where 2 ×re (re = particle interaction radius) is assigned to all particles in the transition region; and varied scheme, where re and 2 ×re are assigned to the central and edged particles in the transition region respectively. Numerical examples, including curvature calculation for static circle and ellipse interfaces, deformation of square droplet to a circle (2D and 3D), droplet deformation in shear flow, and droplet coalescence, are simulated to verify the CCSF model and compare its performance with those of other methods. The CCSF model with the fixed scheme is proven to produce the most accurate curvature and lowest parasitic currents among the tested methods.

  18. Topology Optimization - Improved Checker-Board Filtering With Sharp Contours

    DEFF Research Database (Denmark)

    Pedersen, Christian Gejl; Lund, Jeppe Jessen; Damkilde, Lars

    2006-01-01

    In topology optimization it is mandatory to use a filtering technique in order to prevent checker-boarder solutions. The paper examines a new filtering principle and demonstrates an improved sharpness in the contours. This was not realized in the original proposal of the filter. Furthermore...

  19. A method of dealing polygon's self-intersection contour in SLA

    Institute of Scientific and Technical Information of China (English)

    GAO Yong-qiang; MO Jian-hua; HUANG Shu-huai

    2007-01-01

    The contour of the slices of SLA parts is composed of a great deal of small lines. When offsetting the contour to compensate for the radius of laser spot, many self-intersection contours come into being, which decrease the precision of formed parts. A new lemma to judge the local self-intersection contour and the global self-intersection contour separately is put forward, according to which self-intersection contour can be removed reliably. Meanwhile, a new beam offsetting algorithm for SLA parts is described, which brings about good results in the practical manufacturing process.

  20. The role of "contrast enhancement" in the detection and appearance of visual contours.

    Science.gov (United States)

    Hess, R F; Dakin, S C; Field, D J

    1998-03-01

    We test the proposition that the appearance and detection of visual contours is based on an increase in the perceived contrast of contour elements. First we show that detection of contours is quite possible in the presence of very high levels of variability in contrast. Second we show that inclusion in a contour does not induce Gabor patches to appear to be of higher contrast than patches outside of a contour. These results suggest that, contrary to a number of current models, contrast or its assumed physiological correlate (the mean firing rate of early cortical neurons) is not the determining information for identifying the contour.

  1. Ladder contours are undetectable in the periphery: a crowding effect?

    Science.gov (United States)

    May, Keith A; Hess, Robert F

    2007-10-29

    We studied the perceptual integration of contours consisting of Gabor elements positioned along a smooth path, embedded among distractor elements. Contour elements either formed tangents to the path ("snakes") or were perpendicular to it ("ladders"). Perfectly straight snakes and ladders were easily detected in the fovea but, at an eccentricity of 6 degrees , only the snakes were detectable. The disproportionate impairment of peripheral ladder detection remained when we brought foveal performance away from ceiling by jittering the orientations of the elements. We propose that the failure to detect peripheral ladders is a form of crowding, the phenomenon observed when identification of peripherally located letters is disrupted by flanking letters. D. G. Pelli, M. Palomares, and N. J. Majaj (2004) outlined a model in which simple feature detectors are followed by integration fields, which are involved in tasks, such as letter identification, that require the outputs of several detectors. They proposed that crowding occurs because small integration fields are absent from the periphery, leading to inappropriate feature integration by large peripheral integration fields. We argue that the "association field," which has been proposed to mediate contour integration (D. J. Field, A. Hayes, & R. F. Hess, 1993), is a type of integration field. Our data are explained by an elaboration of Pelli et al.'s model, in which weak ladder integration competes with strong snake integration. In the fovea, the association fields were small, and the model integrated snakes and ladders with little interference. In the periphery, the association fields were large, and integration of ladders was severely disrupted by interference from spurious snake contours. In contrast, the model easily detected snake contours in the periphery. In a further demonstration of the possible link between contour integration and crowding, we ran our contour integration model on groups of three-letter stimuli

  2. IVR RSA Database

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This database contains trip-level reports submitted by vessels participating in Research Set-Aside projects with IVR reporting requirements.

  3. SU-E-J-129: Atlas Development for Cardiac Automatic Contouring Using Multi-Atlas Segmentation

    Energy Technology Data Exchange (ETDEWEB)

    Zhou, R; Yang, J; Pan, T; Milgrom, S; Pinnix, C; Shi, A; Yang, J; Liu, Y; Nguyen, Q; Gomez, D; Dabaja, B; Balter, P; Court, L; Liao, Z [MD Anderson Cancer Center, Houston, TX (United States)

    2015-06-15

    Purpose: To develop a set of atlases for automatic contouring of cardiac structures to determine heart radiation dose and the associated toxicity. Methods: Six thoracic cancer patients with both contrast and non-contrast CT images were acquired for this study. Eight radiation oncologists manually and independently delineated cardiac contours on the non-contrast CT by referring to the fused contrast CT and following the RTOG 1106 atlas contouring guideline. Fifteen regions of interest (ROIs) were delineated, including heart, four chambers, four coronary arteries, pulmonary artery and vein, inferior and superior vena cava, and ascending and descending aorta. Individual expert contours were fused using the simultaneous truth and performance level estimation (STAPLE) algorithm for each ROI and each patient. The fused contours became atlases for an in-house multi-atlas segmentation. Using leave-one-out test, we generated auto-segmented contours for each ROI and each patient. The auto-segmented contours were compared with the fused contours using the Dice similarity coefficient (DSC) and the mean surface distance (MSD). Results: Inter-observer variability was not obvious for heart, chambers, and aorta but was large for other structures that were not clearly distinguishable on CT image. The average DSC between individual expert contours and the fused contours were less than 50% for coronary arteries and pulmonary vein, and the average MSD were greater than 4.0 mm. The largest MSD of expert contours deviating from the fused contours was 2.5 cm. The mean DSC and MSD of auto-segmented contours were within one standard deviation of expert contouring variability except the right coronary artery. The coronary arteries, vena cava, and pulmonary vein had DSC<70% and MSD>3.0 mm. Conclusion: A set of cardiac atlases was created for cardiac automatic contouring, the accuracy of which was comparable to the variability in expert contouring. However, substantial modification may need

  4. Fast Contour-Tracing Algorithm Based on a Pixel-Following Method for Image Sensors.

    Science.gov (United States)

    Seo, Jonghoon; Chae, Seungho; Shim, Jinwook; Kim, Dongchul; Cheong, Cheolho; Han, Tack-Don

    2016-03-09

    Contour pixels distinguish objects from the background. Tracing and extracting contour pixels are widely used for smart/wearable image sensor devices, because these are simple and useful for detecting objects. In this paper, we present a novel contour-tracing algorithm for fast and accurate contour following. The proposed algorithm classifies the type of contour pixel, based on its local pattern. Then, it traces the next contour using the previous pixel's type. Therefore, it can classify the type of contour pixels as a straight line, inner corner, outer corner and inner-outer corner, and it can extract pixels of a specific contour type. Moreover, it can trace contour pixels rapidly because it can determine the local minimal path using the contour case. In addition, the proposed algorithm is capable of the compressing data of contour pixels using the representative points and inner-outer corner points, and it can accurately restore the contour image from the data. To compare the performance of the proposed algorithm to that of conventional techniques, we measure their processing time and accuracy. In the experimental results, the proposed algorithm shows better performance compared to the others. Furthermore, it can provide the compressed data of contour pixels and restore them accurately, including the inner-outer corner, which cannot be restored using conventional algorithms.

  5. Fast Contour-Tracing Algorithm Based on a Pixel-Following Method for Image Sensors

    Directory of Open Access Journals (Sweden)

    Jonghoon Seo

    2016-03-01

    Full Text Available Contour pixels distinguish objects from the background. Tracing and extracting contour pixels are widely used for smart/wearable image sensor devices, because these are simple and useful for detecting objects. In this paper, we present a novel contour-tracing algorithm for fast and accurate contour following. The proposed algorithm classifies the type of contour pixel, based on its local pattern. Then, it traces the next contour using the previous pixel’s type. Therefore, it can classify the type of contour pixels as a straight line, inner corner, outer corner and inner-outer corner, and it can extract pixels of a specific contour type. Moreover, it can trace contour pixels rapidly because it can determine the local minimal path using the contour case. In addition, the proposed algorithm is capable of the compressing data of contour pixels using the representative points and inner-outer corner points, and it can accurately restore the contour image from the data. To compare the performance of the proposed algorithm to that of conventional techniques, we measure their processing time and accuracy. In the experimental results, the proposed algorithm shows better performance compared to the others. Furthermore, it can provide the compressed data of contour pixels and restore them accurately, including the inner-outer corner, which cannot be restored using conventional algorithms.

  6. Recognizing the authenticity of emotional expressions: F0 contour matters when you need to know.

    Science.gov (United States)

    Drolet, Matthis; Schubotz, Ricarda I; Fischer, Julia

    2014-01-01

    Authenticity of vocal emotion expression affects emotion recognition and brain activity in the so-called Theory of Mind (ToM) network, which is implied in the ability to explain and predict behavior by attributing mental states to other individuals. Exploiting the variability of the fundamental frequency (F0 contour), which varies more (higher contour) in play-acted expressions than authentic ones, we examined whether contour biases explicit categorization toward a particular authenticity or emotion category. Moreover, we tested whether contour modulates blood-oxygen-level dependent (BOLD) response in the ToM network and explored the role of task as a top-down modulator. The effects of contour on BOLD signal were analyzed by contrasting high and low contour stimuli within two previous fMRI studies that implemented emotion and authenticity rating tasks. Participants preferentially categorized higher contour stimuli as play-acted and lower contour stimuli as sad. Higher contour was found to up-regulate activation task-independently in the primary auditory cortex. Stimulus contour and task were found to interact in a network including medial prefrontal cortex, with an increase in BOLD signal for low-contour stimuli during explicit perception of authenticity and an increase for high-contour stimuli during explicit perception of emotion. Contour-induced BOLD effects appear to be purely stimulus-driven in early auditory and intonation perception, while being strongly task-dependent in regions involved in higher cognition.

  7. Differential Timing Attack Against the Software Implementation of RSA%一种针对RSA算法软件应用的差分计时攻击

    Institute of Scientific and Technical Information of China (English)

    陈财森; 王韬; 田军舰

    2011-01-01

    The former timing attack against RSA algorithm is either just in theory research, or taken in experiment under specifical condition. The object of timing attack mostly is smart card. The former has the disadvantage of low feasibility and small range. We aim to overcome the disadvantage. This thesis provides a feasible timing attack scheme, based the differential statistics algorithm and analysis of variance. Finally we take the attack scheme into practice on the software implementation of RSA, the result indicates that our attack scheme has a better feasibility than the former, and also extend the attack object to RSA with different length key.%原有针对一般RSA算法的计时攻击方式不是只在理论上进行研究,就是在某种特定的条件下进行实验,其主要研究对象是智能卡,具有可行性不高、攻击范围狭窄等缺点.在深入研究分析RSA实现算法基础上,结合差分统计分析方法,引入方差分析假设检验,提出一种可行的计时攻击算法,并针对RSA算法的软件应用进行攻击验证,结果表明提出的攻击方案不仅比传统攻击方式具有更高的可行性,而且能够适用于不同密钥长度的攻击.

  8. Contouring Control for a CNC Milling Machine Driven by Direct thrust Controlled Linear Induction Motors

    Directory of Open Access Journals (Sweden)

    Khaled N. Faris

    2015-12-01

    Full Text Available According to various advantages of linear induction motor (LIM, such as high starting thrust force, high speed operation and reduction of mechanical losses, more applications have utilized this type of motors. Direct Thrust Control (DTC technique is considered as one of the most efficient techniques that can be used for LIM. DTC is preferable to give a fast and good dynamic thrust response. So, to improve the accuracy and robustness of contouring control for CNC machine tools, linear induction motors with a direct thrust control technique are introduced for driving these machines. An industry standard motion control system is applied for reducing the tracking error and improving the desired accuracy. Different loading conditions are simulated to validate the reliability and robustness of the introduced system to match the application field. The proposed system is simulated using the MATLAB/SIMULINK Package; simulation results validated both tracking accuracy and robustness of the proposed motion control system for contouring control for a CNC (Computer Numerical Control milling machine.

  9. U.S. Atlantic East Coast bathymetry contours (EGLORIA_CNT)

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — The bathymetric contours, which comprise this GIS data layer, contains contours for the U.S. Atlantic East Coast. The dataset was created for use with the USGS...

  10. Comprehensive contour prediction model of work rolls in hot wide strip mill

    Institute of Scientific and Technical Information of China (English)

    Xiaodong Wang; Quan Yang; Anrui He; Renzhong Wang

    2007-01-01

    The predictive calculation of comprehensive contour of work rolls in the on-line strip shape control model during hot rolling consists of two important parts of wear contour calculation and thermal contour calculation, which have a direct influence on the accuracy of shape control. A statistical wear model and a finite difference thermal contour model of work rolls were described. The comprehensive contour is the equivalence treatment of the sum of grinding, wear, and thermal contours. This comprehensive contour calculation model has been applied successfully in the real on-line strip shape control model. Its high precision has been proved through the large amounts of actual roll profile measurements and theoretical analyses. The hit rates (percent of shape index satisfying requirement) of crown and head flatness of the strips rolled, by using the shape control model, which includes the comprehensive contour calculation model, have about 16% and 10% increase respectively, compared to those of strips rolled by using manual operation.

  11. Calf Contouring with Endoscopic Fascial Release, Calf Implant, and Structural Fat Grafting

    Directory of Open Access Journals (Sweden)

    Ercan Karacaoglu, MD

    2013-08-01

    Conclusions: A novel endoscopic approach for lower leg contouring is discussed. Endoscopic fasciotomy technique with calf implant and structural fat grafting for improved lower leg aesthetics is a simple, effective, reliable, and predictable technique for calf contouring.

  12. U.S. Atlantic East Coast bathymetry contours (EGLORIA_CNT)

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — The bathymetric contours, which comprise this GIS data layer, contains contours for the U.S. Atlantic East Coast. The dataset was created for use with the USGS...

  13. Neural Correlates of the Poggendorff Illusion Driven by Illusory Contour: An fMRI Study

    OpenAIRE

    Qi Chen; Li Li

    2011-01-01

    The Poggendorff illusion is a well-documented geometric illusion that involves the brain's perception of the interaction between oblique lines and object contours: an oblique line is apparently misaligned once interrupted by two parallel contours. This illusion occurs even when the parallel contours are defined subjectively or illusorily. In this fMRI study, we adopted a 4 (type of stimuli: Poggendorff illusion under real contour and its corresponding control condition; Poggendorff illusion u...

  14. Research on Constructing Contours from Regular Terrain Grids Containing Invalid Data

    Institute of Scientific and Technical Information of China (English)

    SU Wei-min; WU Fan

    2004-01-01

    A new method for constructing contours from complicated terrain elevation grids containing invalid data is put forward. By using this method, the topological consistency of contours in groups can be maintained effectively and the contours can be drawn smoothly based on boundaries pre-searching and local correction. An experimental example is given to demonstrate that the contours constructed by this method are of good quality.

  15. The effect of contouring variability on dosimetric parameters for brain metastases treated with stereotactic radiosurgery.

    Science.gov (United States)

    Stanley, Julia; Dunscombe, Peter; Lau, Harold; Burns, Paul; Lim, Gerald; Liu, Hong-Wei; Nordal, Robert; Starreveld, Yves; Valev, Boris; Voroney, Jon-Paul; Spencer, David P

    2013-12-01

    To quantify the effect of contouring variation on stereotactic radiosurgery plan quality metrics for brain metastases. Fourteen metastases, each contoured by 8 physicians, formed the basis of this study. A template-based dynamic conformal 5-arc dose distribution was developed for each of the 112 contours, and each dose distribution was applied to the 7 other contours in each patient set. Radiation Therapy Oncology Group (RTOG) plan quality metrics and the Paddick conformity index were calculated for each of the 896 combinations of dose distributions and contours. The ratio of largest to smallest contour volume for each metastasis varied from 1.25 to 4.47, with a median value of 1.68 (n=8). The median absolute difference in RTOG conformity index between the value for the reference contour and the values for the alternative contours was 0.35. The variation of the range of conformity index for all contours for a given tumor varied with the tumor size. The high degree of interobserver contouring variation strongly suggests that peer review or consultation should be adopted to standardize tumor volume prescription. Observer confidence was not reflected in contouring consistency. The impact of contouring variability on plan quality metrics, used as criteria for clinical trial protocol compliance, was such that the category of compliance was robust to interobserver effects only 70% of the time. Copyright © 2013 Elsevier Inc. All rights reserved.

  16. Fast Graph Partitioning Active Contours for Image Segmentation Using Histograms

    Directory of Open Access Journals (Sweden)

    Nath SumitK

    2009-01-01

    Full Text Available Abstract We present a method to improve the accuracy and speed, as well as significantly reduce the memory requirements, for the recently proposed Graph Partitioning Active Contours (GPACs algorithm for image segmentation in the work of Sumengen and Manjunath (2006. Instead of computing an approximate but still expensive dissimilarity matrix of quadratic size, , for a 2D image of size and regular image tiles of size , we use fixed length histograms and an intensity-based symmetric-centrosymmetric extensor matrix to jointly compute terms associated with the complete dissimilarity matrix. This computationally efficient reformulation of GPAC using a very small memory footprint offers two distinct advantages over the original implementation. It speeds up convergence of the evolving active contour and seamlessly extends performance of GPAC to multidimensional images.

  17. Region-based active contour with noise and shape priors

    CERN Document Server

    Lecellier, François; Fadili, Jalal; Aubert, Gilles; Revenu, Marinette; Saloux, Eric

    2008-01-01

    In this paper, we propose to combine formally noise and shape priors in region-based active contours. On the one hand, we use the general framework of exponential family as a prior model for noise. On the other hand, translation and scale invariant Legendre moments are considered to incorporate the shape prior (e.g. fidelity to a reference shape). The combination of the two prior terms in the active contour functional yields the final evolution equation whose evolution speed is rigorously derived using shape derivative tools. Experimental results on both synthetic images and real life cardiac echography data clearly demonstrate the robustness to initialization and noise, flexibility and large potential applicability of our segmentation algorithm.

  18. Segmentation of Coronal Holes Using Active Contours Without Edges

    CERN Document Server

    Boucheron, L E; McAteer, R T J

    2016-01-01

    An application of active contours without edges is presented as an efficient and effective means of extracting and characterizing coronal holes. Coronal holes are regions of low-density plasma on the Sun with open magnetic field lines. As the source of the fast solar wind, the detection and characterization of these regions is important for both testing theories of their formation and evolution and from a space weather perspective. Coronal holes are detected in full disk extreme ultraviolet (EUV) images of the corona obtained with the Solar Dynamics Observatory Atmospheric Imaging Assembly (SDO/AIA). The proposed method detects coronal boundaries without determining any fixed intensity value in the data. Instead, the active contour segmentation employs an energy-minimization in which coronal holes are assumed to have more homogeneous intensities than surrounding active regions and quiet Sun. The segmented coronal holes tend to correspond to unipolar magnetic regions, are consistent with concurrent solar wind ...

  19. BABEL - A method for digitization and restoration of contour maps

    Science.gov (United States)

    Westphalen, Gernot

    1995-03-01

    We have developed BABEL as a method for digitization and restoration of contour maps. The results of the comparison between restoration and template are encouraging and first applications are proving very useful. The restoration method is now quite flexible and fast. The result is available as a standard fits file, so that the restored map can be transferred into various coordinate systems and projections and can be used for further digital processing, e.g. for comparison of older radio data with new infrared or X-ray data. So far we have digitized various HI line and 11.1 cm continuum contour maps, for which we know that the original digital data were lost or did never exist in a machine readable format.

  20. Diffusion tensor driven contour closing for cell microinjection targeting.

    Science.gov (United States)

    Becattini, Gabriele; Mattos, Leonardo S; Caldwell, Darwin G

    2010-01-01

    This article introduces a novel approach to robust automatic detection of unstained living cells in bright-field (BF) microscope images with the goal of producing a target list for an automated microinjection system. The overall image analysis process is described and includes: preprocessing, ridge enhancement, image segmentation, shape analysis and injection point definition. The developed algorithm implements a new version of anisotropic contour completion (ACC) based on the partial differential equation (PDE) for heat diffusion which improves the cell segmentation process by elongating the edges only along their tangent direction. The developed ACC algorithm is equivalent to a dilation of the binary edge image with a continuous elliptic structural element that takes into account local orientation of the contours preventing extension towards normal direction. Experiments carried out on real images of 10 to 50 microm CHO-K1 adherent cells show a remarkable reliability in the algorithm along with up to 85% success for cell detection and injection point definition.

  1. Effects of Contoured Pallets on AMC Mission Efficiency

    Science.gov (United States)

    2011-06-01

    airlines. It postulated that national security would benefit from keeping commercial airlines as a viable source of airlift (Donovan, 2011). After the...Research Project, AFIT/ GMO /ENS/04I-01, Air Force Institute of Technology, Wright-Patterson AFB, OH McNabb, Duncan J. (2009). Statement of General Duncan...analysis of the benefits in producing more contoured pallets AMC and USTRANSCOM can increase the efficiency of channel airlift while boosting civilian

  2. Yet another method for triangulation and contouring for automated cartography

    Science.gov (United States)

    De Floriani, L.; Falcidieno, B.; Nasy, G.; Pienovi, C.

    1982-01-01

    An algorithm is presented for hierarchical subdivision of a set of three-dimensional surface observations. The data structure used for obtaining the desired triangulation is also singularly appropriate for extracting contours. Some examples are presented, and the results obtained are compared with those given by Delaunay triangulation. The data points selected by the algorithm provide a better approximation to the desired surface than do randomly selected points.

  3. Contour classification in thermographic images for detection of breast cancer

    Science.gov (United States)

    Okuniewski, Rafał; Nowak, Robert M.; Cichosz, Paweł; Jagodziński, Dariusz; Matysiewicz, Mateusz; Neumann, Łukasz; Oleszkiewicz, Witold

    2016-09-01

    Thermographic images of breast taken by the Braster device are uploaded into web application which uses different classification algorithms to automatically decide whether a patient should be more thoroughly examined. This article presents the approach to the task of classifying contours visible on thermographic images of breast taken by the Braster device in order to make the decision about the existence of cancerous tumors in breast. It presents the results of the researches conducted on the different classification algorithms.

  4. File Encryption System Based on Triple DES and RSA%基于Triple DES与RSA的文件加密系统

    Institute of Scientific and Technical Information of China (English)

    胡振

    2012-01-01

    Comparing the characteristics of symmetric cryptography and asymmetric cryptography, this paper outlines the basic principles of the Triple DES algorithm and the RSA algorithm. On the basis of a detailed analysis of issues related to file security and in-depth study on . NET Framework encryption algorithm class, this paper proposes the file encryption scheme on the combination of the Triple DES algorithm and the RSA algorithm, designs the system' s overall structure and the basic process, then the system is realized with VB. NET. After practice, the results show that the system is simple and convenient for file encryption.%比较对称密码体制与非对称密码体制的特点,简述Triple DES算法与RSA算法的基本原理.在详细分析文件安全的相关问题和深入研究.NET Framework密码算法类的基础上,提出Triple DES算法与RSA算法结合运用的文件加密方案,设计系统的总体结构和基本流程,并以VB.NET实现了基于Triple DES与RSA的文件加密系统.实践表明,用本系统进行文件加密简单而方便.

  5. 基于RSA的数字图像加密算法%An Encryption Algorithm for Digital Image Based on RSA System

    Institute of Scientific and Technical Information of China (English)

    杨昔阳; 李志伟

    2009-01-01

    It proposes a novel encryption method for digital image based on an Arnold scrambling transform, a chaos encryption algorithm and RSA encryption system. The parameters of the Arnold transform and chaos encryption algorithm are encrypted by RSA system and stored in LSB of an image to ensure the security in transmission. The example in this paper shows that the proposed method is an efficient way to encrypt a digital image.%提出一种基于RSA公钥、Arnold置乱变换和混沌加密算法相结合的公开密钥数字图像加密体制,利用客户的公钥对Arnold置乱变换和混沌序列初值进行RSA加密,确保了只有合法用户才能获取置乱参数信息并将图像复原.RSA对参数的加密信息隐藏于图像LSB中,无需另外传递密文,运算简单,具有良好的加密与隐藏效果.

  6. Cache Timing Attack on RSA Sliding Window Algorithm%针对RSA滑动窗口算法的Cache计时攻击

    Institute of Scientific and Technical Information of China (English)

    田军舰; 寇应展; 陈财森; 高靖哲; 曾剑隽

    2011-01-01

    Based on researching RSA signature algorithm and theory of cache timing attack, analyzing the implementation of RSA in OpenSSL0.9.8a, a caching timing attack method is given against the process of accessing initial table in the sliding windows algorithm. Simulation result demonstrates the cache timing attack can get more than 700 bit secret key from 1 024 bit private key and needs less samples compare to the timing attack based on statistic analysis.%研究RSA签名算法和Cache计时攻击原理,分析OpenSSL0.9.8a中的RSA实现过程,针对RSA滑动窗口算法中的访问初始化表操作,提出一种Cache计时攻击方法.实验结果表明,该方法在1次攻击中可获得1 024 bit密钥中700 bit以上的密钥,与传统基于统计方法的计时攻击相比,所需样本更少.

  7. Visual search of illusory contours: an attempt of automatization

    Directory of Open Access Journals (Sweden)

    Gvozdenović Vasilije

    2008-01-01

    Full Text Available Laboratory of Experimental Psychology, University of Belgrade Recent research, which was mostly focused on assessing the types of visual search of illusory contours, showed that visual search is dependent on factors like target configuration and task type. Some experimental research supports the theory of parallel search while other research supports the theory of serial search of illusory contours. The inconsistency is most likely due to the fact that various types of illusory contour configurations were used in set creation. Up to this point, our research indicated that the serial search is used in most cases. Some exceptions of search type have been proven in some modification of task type but nevertheless the search profile remained serial. In this article, we are reporting on two visual search experiments. The first experiment was an investigation of a specific feature of a Kanisza type illusory triangle, orientation. The validity of the profile defined in the first experiment was tested in our second experiment with an attempt to automatize the visual search by the multiplication of the initial experimental trials. Our results confirmed that, regardless of the number of experimental trials, the visual search profile remains serial.

  8. Practical contour segmentation algorithm for small animal digital radiography image

    Science.gov (United States)

    Zheng, Fang; Hui, Gong

    2008-12-01

    In this paper a practical, automated contour segmentation technique for digital radiography image is described. Digital radiography is an imaging mode based on the penetrability of x-ray. Unlike reflection imaging mode such as visible light camera, the pixel brightness represents the summation of the attenuations on the photon thoroughfare. It is not chromophotograph but gray scale picture. Contour extraction is of great importance in medical applications, especially in non-destructive inspection. Manual segmentation techniques include pixel selection, geometrical boundary selection and tracing. But it relies heavily on the experience of the operators, and is time-consuming. Some researchers try to find contours from the intensity jumping characters around them. However these characters also exist in the juncture of bone and soft tissue. The practical way is back to the primordial threshold algorithm. This research emphasizes on how to find the optimal threshold. A high resolution digital radiography system is used to provide the oriental gray scale image. A mouse is applied as the sample of this paper to show the feasibility of the algorithm.

  9. Timing and Estimates of Plio-Pleistocene Sea-Level Highstands from the Republic of South Africa (RSA)

    Science.gov (United States)

    Hearty, Paul; Raymo, Maureen; Sandstrom, Michael; Rovere, Alessio; O'Leary, Michael

    2016-04-01

    The rapid rise in atmospheric CO2 exceeding 400 ppmv is driving an urgent need to better understand past sea level, ice sheet dynamics, and climate change associated with past warmer geological intervals. The LR04 record reveals sustained intervals during the Pliocene (5.6-2.6 Ma) when δ18O exceeded the present levels, indicating a possible decrease in the volume of polar ice sheets. Other shorter intervals of likely decreased ice volume occur during Pleistocene interglacials including MIS 5e, 11, 31, and 37.Here we focus on the middle Pliocene warm period (MPWP; 3.3 to 2.9 Ma), an interval during which Earth experienced CO2 levels around 400 ppmv (Fedorov et al., 2013). The intra-plate coastal margin of western South Africa, a region of relative tectonic stability and relative insensitivity to uncertainty in mantle viscosity as is effects corrections for glacial isostatic adjustment, is a promising region for deriving estimates of eustatic sea level (ESL; thus ice volumes) at the end of the MPWP (Rovere et al., 2014). During a field expedition covering several thousand kilometres along coastlines of western and southern coasts of RSA, we documented the stratigraphy, geomorphology, and geochronology of Pliocene and Pleistocene shorelines with differential GPS providing decimeter scale accuracy to stratigraphic contacts and sea-level indicators. From about twenty sites, precise elevations (as yet uncorrected for GIA) of multiple sea stands were recorded. Strontium isotopes were used to date the shell material from many of the marine sites, but only three sites yielded reliable age data that passed screening criteria for diagenesis. The oldest shoreline evidence, from Cliffs Point on the west coast near the Olifants River, is observed at 34.9 ±0.2 m asl and yields an age 4.70 ± 0.20 Ma; a younger shoreline from the southern coast Bredasdorp site is observed at >24.0 ± 1.5 m asl and yields ages from 3.00 ± 0.45 to 3.55 ± 0.31 Ma, the interval of the MPWP. . A

  10. Effect of Cropping System and Contouring or Download Sowing on Soil Water Erosion under no Tillage

    Science.gov (United States)

    Marioti, J.; Padilha, J.; Bertol, I.; Barbosa, F. T.; Ramos, J. C.; Werner, R. S.; Vidal Vázquez, E.; Tanaka, M. S.

    2012-04-01

    Water erosion is the main responsible factor of soil and water losses, thus also causing soil degradation, especially on agricultural land, and it is also one factor of degradation outside the place of the origin of erosion. No tillage agriculture has been practiced in the last few decades for the purposes of water erosion control in various regions of Brazil. However, it has been shown that no tillage does not adequately control water erosion unless other complementary conservationist practices such as contour tillage or terracement. Although the erosion problem is widely recognized, there are still difficulties in estimating their magnitude, the environmental impact and the economic consequences, especially when it occurs in a conservation system like no tillage. The aim of this study was to quantify runoff and soil losses by water erosion under five different soil tillage treatments at Santa Catarina State, Southern Brazil. A field study was carried out using a rotating-boom rainfall simulator with 64 mmh-1 rainfall intensity for 90 minutes. Four rainfall tests were applied over the experimental period, one in each of the successive soybean and maize crop stages. Both soil cover by surface crop residue and soil cover by soybean and maize plant canopy were measured immediately before each rainfall test. Soil and water losses were smaller when sowing in contour than when sowing downslope. Contouring has promoted an average reduction of 42% in soil losses and 20% in water losses. Maize crop has promoted an average reduction of 19% in soil losses and 12% in water losses, in relation to the soybean crop. Therefore runoff rates and soil losses were higher in the downslope plots and in the soybean crop. Soil cover by previous crop residue was an important factor for reducing soil losses. Runoff rates were influenced by the soil water content before each rainfall test (R2= 0.78). The highest runoff occurred during the third simulated rainfall test, with the 83% of the

  11. Prediction of the rotational state of the humerus by comparing the contour of the contralateral bicipital groove: Method for intraoperative evaluation

    Directory of Open Access Journals (Sweden)

    Se-Jin Park

    2012-01-01

    Full Text Available Background: Accurate reduction of rotational displacement for transverse or comminute fracture of humeral shaft fracture is difficult during operation. The purpose of this study was to evaluate the reliability of the bicipital groove as a point of reference for the prediction of the rotational state of the humerus on two dimensional images of C-arm image intensifier during operation for humeral shaft fractures. Materials and Methods: One hundred subjects, 62 male, 38 female, aged 22-53 years were recruited contralateral bicipital groove on the 45 degrees externally rotational standard anterior-posterior view recorded before surgery. Three observers, watched only contour of bicipital groove in monitor of C-arm image intensification with naked eye without looking at the subject and predicted rotational state of the humerus by comparing the contour of the opposite side of bicipital groove. The angle of discrepancy from real rotational position was then assessed. Results: The mean (SD, angular discrepancy between the neutral point and the predicted angle was 3.4°(±2.7°. A value within 5° was present in 72% of cases. All observations were within 15°. There was no interobserver variation (P = 0.47. The intraclass correlation coefficient (ICC was 0.847. Conclusion: Contour of the bicipital groove on simple radiograph was a useful landmark. Comparing the contour of the bicipital groove in the 45 degrees externally rotational standard view bilaterally, was an effective method for reduction of rotational displacement of the humerus.

  12. Time contour expression of limited range phenomena on stack chart; Jugo chart jo deno kyokuchi gensho jikan contour

    Energy Technology Data Exchange (ETDEWEB)

    Kametani, T.

    1997-05-27

    Time contour expression of limited range phenomena on stack chart is examined for further improvement on the result of the ultimate interpretation in the seismic reflection survey. The policy is made clear from the beginning that local phenomena are to be discussed, and data prior CMP stacking is interpreted in detail. For this purpose, it is effective to make use of the time contour expression in the midpoint-offset plane simultaneously with the CMP and COP panels. For the review of data prior to CMP stacking, it is convenient to use the CMP (CDP) stacking chart in which the data is arranged methodically. In this chart, all the channels which are crude data prior to stacking are plotted on midpoint-offset coordinates, which plane is called the MOD (Midpoint Offset Domain) panel. Various panels can be chosen unrestrictedly, and their mutual relations can be easily grasped. When data points are given a time axis, they can be expressed in a time contour. Studies are conducted about the underground structure, multiple reflection paths divided by it, and characteristics of detour reflection attributable to faults. 4 refs., 9 figs.

  13. A Contour-Guided Deformable Image Registration Algorithm for Adaptive Radiotherapy

    CERN Document Server

    Gu, Xuejun; Wang, Jing; Yordy, John; Mell, Loren; Jia, Xun; Jiang, Steve B

    2013-01-01

    In adaptive radiotherapy, deformable image registration is often conducted between the planning CT and treatment CT (or cone beam CT) to generate a deformation vector field (DVF) for dose accumulation and contour propagation. The auto propagated contours on the treatment CT may contain relatively large errors, especially in low contrast regions. A clinician inspection and editing of the propagated contours are frequently needed. The edited contours are able to meet the clinical requirement for adaptive therapy; however, the DVF is still inaccurate and inconsistent with the edited contours. The purpose of this work is to develop a contour-guided deformable image registration (CG-DIR) algorithm to improve the accuracy and consistency of the DVF for adaptive radiotherapy. Incorporation of the edited contours into the registration algorithm is realized by regularizing the objective function of the original demons algorithm with a term of intensity matching between the delineated structures set pairs. The CG-DIR a...

  14. RBF neural network and active circles based algorithm for contours extraction

    Institute of Scientific and Technical Information of China (English)

    Zhou Zhiheng; Zeng Delu; Xie Shengli

    2007-01-01

    For the contours extraction from the images, active contour model and self-organizing map based approach are popular nowadays. But they are still confronted with the problems that the optimization of energy function will trap in local minimums and the contour evolutions greatly depend on the initial contour selection. Addressing to these problems, a contours extraction algorithm based on RBF neural network is proposed here. A series of circles with adaptive radius and center is firstly used to search image feature points that are scattered enough. After the feature points are clustered, a group of radial basis functions are constructed. Using the pixels' intensities and gradients as the input vector, the final object contour can be obtained by the predicting ability of the neural network. The RBF neural network based algorithm is tested on three kinds of images, such as changing topology, complicated background, and blurring or noisy boundary. Simulation results show that the proposed algorithm performs contours extraction greatly.

  15. Motion detection, noise reduction, texture suppression, and contour enhancement by spatiotemporal Gabor filters with surround inhibition

    NARCIS (Netherlands)

    Petkov, Nicolai; Subramanian, Easwar

    2007-01-01

    We study the orientation and speed tuning properties of spatiotemporal three-dimensional (3D) Gabor and motion energy filters as models of time-dependent receptive fields of simple and complex cells in the primary visual cortex (V1). We augment the motion energy operator with surround suppression to

  16. Efectos de 2 Tipos de Entrenamiento Interválico de Alta Intensidad en la Habilidad para Realizar Esfuerzos Máximos (RSA Durante una Pretemporada de Fútbol

    Directory of Open Access Journals (Sweden)

    Alejandro Rodríguez Fernández

    2014-01-01

    Full Text Available El trabajo de pretemporada persigue mejorar el rendimiento del futbolista tanto en lo referente a la habilidad para realizar esfuerzos máximos como a su capacidad aeróbica y de recuperación. El objetivo de este estudio fue comparar durante una pretemporada los efectos de 2 programas de entrenamiento interválicos con series de diferente duración en la habilidad de repetir sprints (RSA. Diecinueve jugadores de fútbol con valores medios ± SD de 20,9 ± 1,6 años de edad; 68,8 ± 5,1 Kg de peso; 176,1 ± 5,1 cm de altura; y 9,6 ± 2,4% de grasa corporal fueron asignados al azar al grupo de Speed Endurance Training (SET para realizar 2x10 min con 10, 15 y 20 s al 100% con 30, 45 y 60 s de recuperación (n = 9, o al grupo High Interval Training (HIT para realizar 4x4 min al 95% FCmax (n = 10. Un test RSA de 8x30 m con 25 s de recuperación activa fue realizado antes y después de la intervención (10 sesiones de entrenamiento junto con un Yo-Yo Intermittent Recovery Test level 1 en la evaluación inicial. Tanto SET como HIT ven incrementado su rendimiento de forma significativa (p < 0,05 en RSAmejor (3,12% y 3,59% respectivamente y muy significativamente (p < 0,01 en RSAmedia (3,00% y 3,91% y RSAtotal (3,12% y 4,08%, pero sin cambios significativos en los índices de fatiga (Sdec y Change. Estos resultados demuestran que tanto la intervención SET como HIT se han mostrado útiles para aumentar el rendimiento en algunas de las variables determinantes en el test RSA, durante el periodo de pretemporada.

  17. Efficacy of injections of phosphatidylcholine into fat deposits-a non-surgical alternative to liposuction in body-contouring

    Directory of Open Access Journals (Sweden)

    Karl-G Heinrich

    2005-01-01

    Full Text Available Injecting phosphatidylcholine has been used in South America as a non-surgical treatment in body contouring. The objective of this study was to demonstrate the efficacy of injecting phosphatidylcholine in the reduction of localised fat deposits. 86 patients were included in the study. Patients received 1-3 treatments in localised fat deposits in various areas of the body using phosphatidylcholine. After treatment with phosphatidylcholine (250 mg / 5 ml, fat deposits show an average circumferential reduction per application of 2.70 cm. No patient showed irregularities, dimples or any serious side effect after treatment. Results remained stable during the time of follow up. All patients showed remarkable reductions of the fat deposits treated with phosphatidylcholine. Using the correct technique, injecting phosphatidylcholine may be a safe and efficacious alternative to liposuction in patients objecting to surgery.

  18. Terrain Contour Matching (TERCOM): A Cruise Missile Guidance Aid

    Science.gov (United States)

    Golden, Joe P.

    1980-12-01

    The Cruise Missile is guided by an inertial guidance system aided by an updating technique called Terrain Contour Matching (TERCOM). Chance-Vought first proposed the terrain correlation technique in the late 1950's. Since that time TERCOM has evolved into a reliable, accurate, all weather, day and night method of position fixing and updating for cruise missiles. A brief history of TERCOM development will be presented giving results where possible. A description of TERCOM and how is works will be discussed. A snapshot of the present TERCOM status and future planned developments will be addressed.

  19. Laser Welding Of Contoured Thin-Wall Housings

    Science.gov (United States)

    Spiegel, Lyle B.; Oleksiak, Carl E.

    1991-01-01

    Superalloy parts joined with less distortion. Carbon dioxide laser beam directed by optics in numerically controlled robot arm welds shell-type turbopump housings having complicated shapes. 5-kW laser, following single programmed three-dimensional pass, produces high-quality, full-penetration weld pass in age-hardenable nickel superalloy. Operator easily programs robot by using teaching pendant to track weld joint and keeps laser focused on workpiece while following contour of shell. Shells welded in rapid succession, with minimal change in setup for each.

  20. Control of Open Contour Formations of Autonomous Underwater Vehicles

    Directory of Open Access Journals (Sweden)

    Uwe Zimmer

    2008-11-01

    Full Text Available In this paper, we propose a distributed elastic behaviour for a deformable chain-like formation of small autonomous underwater vehicles with the task of forming special shapes which have been explicitly defined or are defined by some iso-contour of an environmental concentration field. In the latter case, the formation has to move in such a way as to meet certain formation parameters as well as adapt to the iso-line. We base our controller on our previous models (for manually controlled end points using general curve evolution theory but will also propose appropriate motions for the end robots of an open chain.

  1. SOl-based radial-contour-mode micromechanical disk resonator

    Institute of Scientific and Technical Information of China (English)

    Jia Yingqian; Zhao Zhengping; Yang Yongjun; Hu Xiaodong; Li Qian

    2011-01-01

    This paper reports a radial-contour-mode micromechanical disk resonator for radio frequency applications.This disk resonator with a gold plated layer as the electrodes,was prepared on a silicon-on-insulator wafer,which is supported by an anchor on another silicon wafer through Au-Au thermo-compression bonding.The gap between the disk and the surrounding gold electrodes is 100 nm.The radius of the disk is 20 μm and the thickness is 4.5μm.In results,the resonator shows a resonant frequency of 143 MHz and a quality factor of 5600 in vacuum.

  2. Contour tracking and corner detection in a logic programming environment

    DEFF Research Database (Denmark)

    Bell, Benjamin; Pau, L. F.

    1990-01-01

    The added functionality such as contour tracking and corner detection which logic programming lends to standard image operators is described. An environment for implementing low-level imaging operations with Prolog predicates is considered. Within this environment, higher-level image predicates...... has been very good in many more complex images, as it allows for feedback both ways between sensor input and symbolic models. More important is the parameter selection capability in a dynamic version where background properties change. The authors present examples of Prolog predicates for performing...

  3. Pulse contour-derived cardiac output in hemodialysis patients

    DEFF Research Database (Denmark)

    Cordtz, Joakim; Ladefoged, Soeren D

    2010-01-01

    Reliable methods for cardiac output determination are essential for studying the pathophysiology of intradialytic hypotension. Use of the current gold standard, the Transonic monitor, requires an arteriovenous fistula. We wished to verify the accuracy of a method based on finger pulse contour...... analysis, namely the Finometer monitor (FNM) for further use on patients dialyzing on a central vascular catheter. Fifty simultaneous cardiac output measurements were obtained during hemodialysis sessions in 25 patients. The internal variability of the FNM measurements was assessed by comparing 24 pairs...

  4. Differences in Radiotherapy Delivery and Outcome Due to Contouring Variation

    DEFF Research Database (Denmark)

    Hollensen, Christian; Persson, Gitte; Højgaard, Liselotte;

    2012-01-01

    segmentation methods also produce different results. There is no consensus on how to account for the contouring uncertainty, but has been suggested to incorporate it into the planning target volume (PTV) margin. Current recipes for the PTV margin are based on normal distribution assumptions and are more......Gross tumor volume (GTV) delineation is central for radiotherapy planning. It provides the basis of the clinical target volume and, ultimately, the planning target volume which is used for dose optimization. Manual GTV delineations are prone to intra- and inter-observer variation and automatic...

  5. The Effect of Local Orientation Change on the Detection of Contours Defined by Constant Curvature: Psychophysics and Image Statistics

    Science.gov (United States)

    Khuu, Sieu K.; Cham, Joey; Hayes, Anthony

    2017-01-01

    In the present study, we investigated the detection of contours defined by constant curvature and the statistics of curved contours in natural scenes. In Experiment 1, we examined the degree to which human sensitivity to contours is affected by changing the curvature angle and disrupting contour curvature continuity by varying the orientation of end elements. We find that (1) changing the angle of contour curvature decreased detection performance, while (2) end elements oriented in the direction (i.e., clockwise) of curvature facilitated contour detection regardless of the curvature angle of the contour. In Experiment 2 we further established that the relative effect of end—element orientation on contour detection was not only dependent on their orientation (collinear or cocircular), but also their spatial separation from the contour, and whether the contour shape was curved or not (i.e., C-shaped or S-shaped). Increasing the spatial separation of end-elements reduced contour detection performance regardless of their orientation or the contour shape. However, at small separations, cocircular end-elements facilitated the detection of C-shaped contours, but not S-shaped contours. The opposite result was observed for collinear end-elements, which improved the detection of S- shaped, but not C-shaped contours. These dissociative results confirmed that the visual system specifically codes contour curvature, but the association of contour elements occurs locally. Finally, we undertook an analysis of natural images that mapped contours with a constant angular change and determined the frequency of occurrence of end elements with different orientations. Analogous to our behavioral data, this image analysis revealed that the mapped end elements of constantly curved contours are likely to be oriented clockwise to the angle of curvature. Our findings indicate that the visual system is selectively sensitive to contours defined by constant curvature and that this might

  6. The Poggendorff illusion driven by real and illusory contour: Behavioral and neural mechanisms.

    Science.gov (United States)

    Shen, Lu; Zhang, Ming; Chen, Qi

    2016-05-01

    The Poggendorff illusion refers to the phenomenon that the human brain misperceives a diagonal line as being apparently misaligned once the diagonal line is interrupted by two parallel edges, and the size of illusion is negatively correlated with the angle of interception of the oblique, i.e. the sharper the oblique angle, the larger the illusion. This optical illusion can be produced by both real and illusory contour. In this fMRI study, by parametrically varying the oblique angle, we investigated the shared and specific neural mechanisms underlying the Poggendorff illusion induced by real and illusory contour. At the behavioral level, not only the real but also the illusory contours were capable of inducing significant Poggendorff illusion. The size of illusion induced by the real contour, however, was larger than that induced by the illusory contour. At the neural level, real and illusory contours commonly activated more dorsal visual areas, and the real contours specifically activated more ventral visual areas. More importantly, examinations on the parametric modulation effects of the size of illusion revealed the specific neural mechanisms underlying the Poggendorff illusion induced by the real and the illusory contours, respectively. Left precentral gyrus and right middle occipital cortex were specifically involved in the Poggendorff illusion induced by the real contour. On the other hand, bilateral intraparietal sulcus (IPS) and right lateral occipital complex (LOC) were specifically involved in the Poggendorff illusion induced by the illusory contour. Functional implications of the above findings were further discussed.

  7. An automated workflow for patient-specific quality control of contour propagation

    Science.gov (United States)

    Beasley, William J.; McWilliam, Alan; Slevin, Nicholas J.; Mackay, Ranald I.; van Herk, Marcel

    2016-12-01

    Contour propagation is an essential component of adaptive radiotherapy, but current contour propagation algorithms are not yet sufficiently accurate to be used without manual supervision. Manual review of propagated contours is time-consuming, making routine implementation of real-time adaptive radiotherapy unrealistic. Automated methods of monitoring the performance of contour propagation algorithms are therefore required. We have developed an automated workflow for patient-specific quality control of contour propagation and validated it on a cohort of head and neck patients, on which parotids were outlined by two observers. Two types of error were simulated—mislabelling of contours and introducing noise in the scans before propagation. The ability of the workflow to correctly predict the occurrence of errors was tested, taking both sets of observer contours as ground truth, using receiver operator characteristic analysis. The area under the curve was 0.90 and 0.85 for the observers, indicating good ability to predict the occurrence of errors. This tool could potentially be used to identify propagated contours that are likely to be incorrect, acting as a flag for manual review of these contours. This would make contour propagation more efficient, facilitating the routine implementation of adaptive radiotherapy.

  8. An automated workflow for patient-specific quality control of contour propagation.

    Science.gov (United States)

    Beasley, William J; McWilliam, Alan; Slevin, Nicholas J; Mackay, Ranald I; van Herk, Marcel

    2016-12-21

    Contour propagation is an essential component of adaptive radiotherapy, but current contour propagation algorithms are not yet sufficiently accurate to be used without manual supervision. Manual review of propagated contours is time-consuming, making routine implementation of real-time adaptive radiotherapy unrealistic. Automated methods of monitoring the performance of contour propagation algorithms are therefore required. We have developed an automated workflow for patient-specific quality control of contour propagation and validated it on a cohort of head and neck patients, on which parotids were outlined by two observers. Two types of error were simulated-mislabelling of contours and introducing noise in the scans before propagation. The ability of the workflow to correctly predict the occurrence of errors was tested, taking both sets of observer contours as ground truth, using receiver operator characteristic analysis. The area under the curve was 0.90 and 0.85 for the observers, indicating good ability to predict the occurrence of errors. This tool could potentially be used to identify propagated contours that are likely to be incorrect, acting as a flag for manual review of these contours. This would make contour propagation more efficient, facilitating the routine implementation of adaptive radiotherapy.

  9. Body contouring after obesity surgery is associated with a weight loss benefit among patients.

    Science.gov (United States)

    Agarwal, Shailesh; Shenaq, Deana; Teven, Chad M; Prachand, Vivek; Roughton, Michelle; Zachary, Lawrence

    2017-09-01

    Patients who undergo obesity surgery often require body contouring procedures to eliminate excess skin. Recent studies suggest that body contouring surgery may provide psychological benefits to patients after obesity surgery. However, it remains unclear how body contouring may affect weight loss maintenance after obesity surgery. This is a retrospective review of patients who underwent obesity surgery with or without body contouring at a single institution from 2000 to 2005. Charts were reviewed for demographic, medical, and surgical information. The primary outcome of interest was the difference in weight loss maintenance among patients who underwent body contouring versus those who did not. A total of 318 patients were included for analysis in this study, of which 70 underwent obesity surgery with body contouring and 248 underwent obesity surgery without body contouring. The mean change in BMI among patients who did not undergo body contouring was 19.7 kg/m(2). The mean change in BMI among patients who underwent body contouring was 22.1 kg/m(2). Among patients who underwent body contouring surgery, 2.9% (2/70) of patients did not maintain at least a 20% decrease in body weight during the entire follow-up period (mean follow-up time 92.2 months). Among patients who did not undergo body contouring surgery, 10% (25/248) of patients did not maintain at least a 20% decrease in body weight during the entire follow-up period (mean follow-up time 39.0 months) (χ(2) = 3.67, p = 0.055). Body contouring surgery may have a positive effect on weight loss maintenance after body contouring determined from the mean weight change and on percentage of patients who maintain at least a 20% decrease in body weight. Copyright © 2017. Published by Elsevier Ltd.

  10. 转化RSA为氢化可的松的新月弯胞霉筛选%SCREENING OF CURVULARIA LNATA WITH THE ABILITY OF BIOCONVERTING RSA TO HYDROCORTISONE SCREENING OF CURVULARIA LNATA WITH THE ABILITY OF BIOCONVERTING RSA TO HYDROCORTISONE

    Institute of Scientific and Technical Information of China (English)

    杜连祥; 王敏; 王赓; 孙烨

    2001-01-01

    A strain C4 with ability of bioconversion from steroid RSA to hydrocortisone was selected fron the soil sample. It was identifide as Cuvularia Iunata according its morphological characters of clump and individuals. The optimum culture medium was established by orthogonal experiments :glucose 10g ,soybean powder 10g,water 1000mL, pH6.5. Determined by silica gel chromatography and high-performance liquid chromatography, the bioconversion ratio of hydrocortisone was 34%. At the same tine, the percentage change of RSA,hydrocortisone and other byproducts were measured during the course of bioconversion.%从土样中筛选到1株能转化甾体化合物RSA(17α-羟基孕甾-4-烯-3,20-二酮-21-醋酸酯)生成氢可的松(11β,17a,2l-三羟基孕甾-4-烯-3,20-二酮)的C4菌株,经菌落形态与个体形态观察,初步鉴定为新月弯胞霉(curvularia lunata)。正交实验确定该菌株的最适培养基为:葡萄糖10g,黄豆粉10g,自来水1000mL,pH6.5.经硅胶层析和高交液相色谱测定,氢化可的松转化率为34%。同时还测定了转化过程中RSA、氢化可的松及其它副产物的百分含量的变化。

  11. 基于新月柄杆菌RsaA外运机制的EspA及EspA-IL-24融合蛋白胞外分泌表达研究%Study on Extracellular Expression of EspA and EspA-IL-24 Proteins in Escherichia coli Following RsaA Exportation Mechanism of Caulobacter crescentus

    Institute of Scientific and Technical Information of China (English)

    宁亚蕾; 周立雄; 毛旭虎; 张卫军; 程琰; 余抒; 邹全明

    2008-01-01

    目的:实现大肠杆菌分泌蛋白(Esp)A及EspA与白细胞介素(IL)-24融合蛋白的胞外分泌表达,进一步验证基于新月柄杆菌RsaA外运机制的原核胞外分泌表达载体系统的有效性和通用性,并改造优化该系统.方法:利用分子克隆手段,按RsaA分泌系统操纵子组织方式,将获得的RsaA系统元件编码序列和异源调控序列克隆至pQE30骨架质粒,构建新的胞外分泌表达质粒pQABP2S;以大肠杆菌为宿主菌诱导表达EspA及EspA-IL-24融合蛋白,并通过Western blot检测目标蛋白在培养上清中的表达.结果:获得了新的胞外分泌表达载体pQABP2S;与对照相比,该载体宿主系统培养上清中目标蛋白EspA及EspA-IL-24的表达量明显增加.结论:在大肠杆菌中通过RsaA分泌系统可实现分子大小不同的EspA及EspA-IL-24融合蛋白的特异性分泌表达,进一步证实该分泌表达策略的有效性和通用性;调整调控序列以优化分泌系统的尝试,为此类基因工程技术平台的开发提供了借鉴.

  12. Theory on the molecular characteristic contour (II)--Molecular intrinsic characteristic contours of several typical organic molecules

    Institute of Scientific and Technical Information of China (English)

    GONG; Lidong; ZHAO; Dongxia; YANG; Zhongzhi

    2005-01-01

    The molecular intrinsic characteristic contour (MICC) is defined based on the classical turning point of electron movement in a molecule. Three typical organic molecules, I.e. Methane, methanol and formic acid, were employed as examples for detailed introduction of our method. Investigations on the cross-sections of MICC provide important information about atomic size changing in the process of forming molecules. The electron density distributions on the MICCs of these molecules were calculated and shown for the first time. Results showed that the electron density distribution on the MICC correlates closely with molecular chemical properties, and it provides a new insight into molecular boundary.

  13. Pupil segmentation using active contour with shape prior

    Science.gov (United States)

    Ukpai, Charles O.; Dlay, Satnam S.; Woo, Wai L.

    2015-03-01

    Iris segmentation is the process of defining the valid part of the eye image used for further processing (feature extraction, matching and decision making). Segmentation of the iris mostly starts with pupil boundary segmentation. Most pupil segmentation techniques are based on the assumption that the pupil is circular shape. In this paper, we propose a new pupil segmentation technique which combines shape, location and spatial information for accurate and efficient segmentation of the pupil. Initially, the pupil's position and radius is estimated using a statistical approach and circular Hough transform. In order to segment the irregular boundary of the pupil, an active contour model is initialized close to the estimated boundary using information from the first step and segmentation is achieved using energy minimization based active contour. Pre-processing and post-processing were carried out to remove noise and occlusions respectively. Experimental results on CASIA V1.0 and 4.0 shows that the proposed method is highly effective at segmenting irregular boundaries of the pupil.

  14. Fast Virtual Stenting with Active Contour Models in Intracranical Aneurysm.

    Science.gov (United States)

    Zhong, Jingru; Long, Yunling; Yan, Huagang; Meng, Qianqian; Zhao, Jing; Zhang, Ying; Yang, Xinjian; Li, Haiyun

    2016-02-15

    Intracranial stents are becoming increasingly a useful option in the treatment of intracranial aneurysms (IAs). Image simulation of the releasing stent configuration together with computational fluid dynamics (CFD) simulation prior to intervention will help surgeons optimize intervention scheme. This paper proposed a fast virtual stenting of IAs based on active contour model (ACM) which was able to virtually release stents within any patient-specific shaped vessel and aneurysm models built on real medical image data. In this method, an initial stent mesh was generated along the centerline of the parent artery without the need for registration between the stent contour and the vessel. Additionally, the diameter of the initial stent volumetric mesh was set to the maximum inscribed sphere diameter of the parent artery to improve the stenting accuracy and save computational cost. At last, a novel criterion for terminating virtual stent expanding that was based on the collision detection of the axis aligned bounding boxes was applied, making the stent expansion free of edge effect. The experiment results of the virtual stenting and the corresponding CFD simulations exhibited the efficacy and accuracy of the ACM based method, which are valuable to intervention scheme selection and therapy plan confirmation.

  15. The contour method cutting assumption: error minimization and correction

    Energy Technology Data Exchange (ETDEWEB)

    Prime, Michael B [Los Alamos National Laboratory; Kastengren, Alan L [ANL

    2010-01-01

    The recently developed contour method can measure 2-D, cross-sectional residual-stress map. A part is cut in two using a precise and low-stress cutting technique such as electric discharge machining. The contours of the new surfaces created by the cut, which will not be flat if residual stresses are relaxed by the cutting, are then measured and used to calculate the original residual stresses. The precise nature of the assumption about the cut is presented theoretically and is evaluated experimentally. Simply assuming a flat cut is overly restrictive and misleading. The critical assumption is that the width of the cut, when measured in the original, undeformed configuration of the body is constant. Stresses at the cut tip during cutting cause the material to deform, which causes errors. The effect of such cutting errors on the measured stresses is presented. The important parameters are quantified. Experimental procedures for minimizing these errors are presented. An iterative finite element procedure to correct for the errors is also presented. The correction procedure is demonstrated on experimental data from a steel beam that was plastically bent to put in a known profile of residual stresses.

  16. A NOVEL FAST MOVING OBJECT CONTOUR TRACKING ALGORITHM

    Institute of Scientific and Technical Information of China (English)

    An Guocheng; Yang Hao; Wu Zhenyang

    2009-01-01

    If a somewhat fast moving object exists in a complicated tracking environment, snake's nodes may fall into the inaccurate local minima. We propose a mean shift snake algorithm to solve this problem. However, if the object goes beyond the limits of mean shift snake module operation in successive sequences, mean shift snake's nodes may also fall into the local minima in their moving to the new object position. This paper presents a motion compensation strategy by using particle filter; therefore a new Particle Filter Mean Shift Snake (PFMSS) algorithm is proposed which combines particle filter with mean shift snake to fulfill the estimation of the fast moving object contour. Firstly, the fast moving object is tracked by particle filter to create a coarse position which is used to initialize the mean shift algorithm. Secondly, the whole relevant motion information is used to compensate the snake's node positions. Finally, snake algorithm is used to extract the exact object contour and the useful information of the object is fed back. Some real world sequences are tested and the results show that the novel tracking method have a good performance with high accuracy in solving the fast moving problems in cluttered background.

  17. Contouring error compensation on a micro coordinate measuring machine

    Science.gov (United States)

    Fan, Kuang-Chao; Wang, Hung-Yu; Ye, Jyun-Kuan

    2011-12-01

    In recent years, three-dimensional measurements of nano-technology researches have received a great attention in the world. Based on the high accuracy demand, the error compensation of measurement machine is very important. In this study, a high precision Micro-CMM (coordinate measuring machine) has been developed which is composed of a coplanar stage for reducing the Abbé error in the vertical direction, the linear diffraction grating interferometer (LDGI) as the position feedback sensor in nanometer resolution, and ultrasonic motors for position control. This paper presents the error compensation strategy including "Home accuracy" and "Position accuracy" in both axes. For the home error compensation, we utilize a commercial DVD pick-up head and its S-curve principle to accurately search the origin of each axis. For the positioning error compensation, the absolute positions relative to the home are calibrated by laser interferometer and the error budget table is stored for feed forward error compensation. Contouring error can thus be compensated if both the compensation of both X and Y positioning errors are applied. Experiments show the contouring accuracy can be controlled to within 50nm after compensation.

  18. Evaluation of solar mirror figure by moire contouring

    Energy Technology Data Exchange (ETDEWEB)

    Griffin, J.W.; Lind, M.A.

    1980-06-01

    Moire topography is applied to the figure assessment of solar mirrors. The technique is demonstrated on component facets of a six-meter diameter, four-meter focal length, parabolic dish collector. The relative ease of experimental implementation and subsequent data analysis suggests distinct advantages over the more established laser ray trace or BCS/ICS technique for many applications. The theoretical and experimental considerations necessary to fully implement moire topography on mirror surfaces are detailed. A procedure to de-specularize the mirror is demonstrated which conserves the surface morphology without damaging the reflective surface. The moire fringe patterns observed for the actual mirror facets are compared with theoretical contours generated for representative dish facets using a computer simulation algorithm. A method for evaluating the figure error of the real facet is presented in which the error parameter takes the form of an average absolute deviation of the surface slope from theoretical. The experimental measurement system used for this study employs a 200 line/inch Ronchi transmission grating. The mirror surface is illuminated by a collimated beam at 60/sup 0/. The fringe observation is performed normal to the grating. These parameters yield contour intervals for the fringe patterns of 0.073 mm. The practical considerations for extending the techniques to higher resolution are discussed.

  19. Segmentation of Coronal Holes Using Active Contours Without Edges

    Science.gov (United States)

    Boucheron, L. E.; Valluri, M.; McAteer, R. T. J.

    2016-10-01

    An application of active contours without edges is presented as an efficient and effective means of extracting and characterizing coronal holes. Coronal holes are regions of low-density plasma on the Sun with open magnetic field lines. The detection and characterization of these regions is important for testing theories of their formation and evolution, and also from a space weather perspective because they are the source of the fast solar wind. Coronal holes are detected in full-disk extreme ultraviolet (EUV) images of the corona obtained with the Solar Dynamics Observatory Atmospheric Imaging Assembly (SDO/AIA). The proposed method detects coronal boundaries without determining any fixed intensity value in the data. Instead, the active contour segmentation employs an energy-minimization in which coronal holes are assumed to have more homogeneous intensities than the surrounding active regions and quiet Sun. The segmented coronal holes tend to correspond to unipolar magnetic regions, are consistent with concurrent solar wind observations, and qualitatively match the coronal holes segmented by other methods. The means to identify a coronal hole without specifying a final intensity threshold may allow this algorithm to be more robust across multiple datasets, regardless of data type, resolution, and quality.

  20. Lateral lower face and neck contouring following burn injury.

    Directory of Open Access Journals (Sweden)

    Sadrollah Motamed

    2015-04-01

    Full Text Available The neck is normally a concave and highly mobile structure. Facial and cervical skin is prone to burn scar contracture because of its thin nature. The goal of treatment is to reconstruct this region to achieve a good aesthetic outcome and also normal neck and chin mobilization. This study was conducted to compare the effect of one row of suture and three rows of suture in critical points of the neck to recreate cervicomandibular angle for better contouring of the neck. A cross-sectional study was performed from July 2006 until August 2010. A total of 65 patients underwent lower lateral face and neck burn scar contracture reconstruction. The mean age of participants was 25.5 years old. After designing a local flap, in 31 patients we applied one row of suture. In 34 patients, we used three rows of suture on each side of the neck incorporation with  the recipient bed and the flap dermis or capsule to recreate a natural lower lateral face and neck contour (P<0.001. The standard deviation in hospitalization was 7 ± 2 days for group A and 6 ± 1 days for group B. In a two years follow-up, no blunting of cervicomandibular angle occurred and three rows of suture were superior according to present findings.

  1. Contoured-gap coaxial guns for imploding plasma liner experiments

    Science.gov (United States)

    Witherspoon, F. D.; Case, A.; Brockington, S.; Cassibry, J. T.; Hsu, S. C.

    2014-10-01

    Arrays of supersonic, high momentum flux plasma jets can be used as standoff compression drivers for generating spherically imploding plasma liners for driving magneto-inertial fusion, hence the name plasma-jet-driven MIF (PJMIF). HyperV developed linear plasma jets for the Plasma Liner Experiment (PLX) at LANL where two guns were successfully tested. Further development at HyperV resulted in achieving the PLX goal of 8000 μg at 50 km/s. Prior work on contoured-gap coaxial guns demonstrated an approach to control the blowby instability and achieved substantial performance improvements. For future plasma liner experiments we propose to use contoured-gap coaxial guns with small Minirailgun injectors. We will describe such a gun for a 60-gun plasma liner experiment. Discussion topics will include impurity control, plasma jet symmetry and topology (esp. related to uniformity and compactness), velocity capability, and techniques planned for achieving gun efficiency of >50% using tailored impedance matched pulse forming networks. Mach2 and UAH SPH code simulations will be included. Work supported by US DOE DE-FG02-05ER54810.

  2. The Contour Mapping Program for Prompt Environmental Radiation Distribution Display

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Uk Jae; Yoo, Dong Han; Kim, Hee Reyoung [Ulsan National Institute of Science and Technology, Ulsan (Korea, Republic of)

    2013-10-15

    For prompt response and consequent measure at the environmental radiation emergency of nuclear installations which include nuclear power plants, needed is rapid and movable monitoring system which can display and analyze distribution of overall environmental radiation around surrounding area. At occurrence of the nuclear emergency including the disastrous accident like the Fukushima Nuclear Power Plants accident or detected radiation in the public city environment, the comprehensive understanding of rapid radiation distribution, which has measurement error, is essential for the quick measuring on the public protection in the surrounding area. For that, 2D and 3D contour mapping method are developed for the distribution of natural radiation, major artificial radiation ({sup 137}Cs, {sup 131}I), and total radiation, which is based on the information which is auto-recognized and interpolated for virtually measured radiation data by using random number generation. Especially, the radiation contour is displayed on the map image of the measured area so that the radiation distribution can be understood at a glance. 2D and 3D mapping programming for the distribution of radiation on the simulated measured radiation data was carried out by using MATLAB language. It showed the operation time of a few ten seconds which was more than 100 times faster than conventional technique. It was thought that the present study could be directly employed for the understanding of rapid and comprehensive radiation distribution on the public environment at the nuclear or radiation emergency.

  3. Segmentation of Coronal Holes Using Active Contours Without Edges

    Science.gov (United States)

    Boucheron, L. E.; Valluri, M.; McAteer, R. T. J.

    2016-09-01

    An application of active contours without edges is presented as an efficient and effective means of extracting and characterizing coronal holes. Coronal holes are regions of low-density plasma on the Sun with open magnetic field lines. The detection and characterization of these regions is important for testing theories of their formation and evolution, and also from a space weather perspective because they are the source of the fast solar wind. Coronal holes are detected in full-disk extreme ultraviolet (EUV) images of the corona obtained with the Solar Dynamics Observatory Atmospheric Imaging Assembly (SDO/AIA). The proposed method detects coronal boundaries without determining any fixed intensity value in the data. Instead, the active contour segmentation employs an energy-minimization in which coronal holes are assumed to have more homogeneous intensities than the surrounding active regions and quiet Sun. The segmented coronal holes tend to correspond to unipolar magnetic regions, are consistent with concurrent solar wind observations, and qualitatively match the coronal holes segmented by other methods. The means to identify a coronal hole without specifying a final intensity threshold may allow this algorithm to be more robust across multiple datasets, regardless of data type, resolution, and quality.

  4. Ups and Downs in Auditory Development: Preschoolers' Sensitivity to Pitch Contour and Timbre.

    Science.gov (United States)

    Creel, Sarah C

    2016-03-01

    Much research has explored developing sound representations in language, but less work addresses developing representations of other sound patterns. This study examined preschool children's musical representations using two different tasks: discrimination and sound-picture association. Melodic contour--a musically relevant property--and instrumental timbre, which is (arguably) less musically relevant, were tested. In Experiment 1, children failed to associate cartoon characters to melodies with maximally different pitch contours, with no advantage for melody preexposure. Experiment 2 also used different-contour melodies and found good discrimination, whereas association was at chance. Experiment 3 replicated Experiment 2, but with a large timbre change instead of a contour change. Here, discrimination and association were both excellent. Preschool-aged children may have stronger or more durable representations of timbre than contour, particularly in more difficult tasks. Reasons for weaker association of contour than timbre information are discussed, along with implications for auditory development. Copyright © 2015 Cognitive Science Society, Inc.

  5. Visually-salient contour detection using a V1 neural model with horizontal connections

    CERN Document Server

    Loxley, P N

    2011-01-01

    A convolution model which accounts for neural activity dynamics in the primary visual cortex is derived and used to detect visually salient contours in images. Image inputs to the model are modulated by long-range horizontal connections, allowing contextual effects in the image to determine visual saliency, i.e. line segments arranged in a closed contour elicit a larger neural response than line segments forming background clutter. The model is tested on 3 types of contour, including a line, a circular closed contour, and a non-circular closed contour. Using a modified association field to describe horizontal connections the model is found to perform well for different parameter values. For each type of contour a different facilitation mechanism is found. Operating as a feed-forward network, the model assigns saliency by increasing the neural activity of line segments facilitated by the horizontal connections. Alternatively, operating as a feedback network, the model can achieve further improvement over sever...

  6. COMPARISON OF THREE DIFFERENT IMAGE FORCES FOR ACTIVE CONTOURS ON ABDOMINAL IMAGE BOUNDARY DETECTION

    Directory of Open Access Journals (Sweden)

    Cherry Galatia Ballangan

    2005-01-01

    Full Text Available Active contour, or snake, is an energy minimizing spline that is useful in image boundary detection. Active contours are stimulated by internal forces, image forces and external forces which maintain the shape of the contours while attract the contours to some desired features, usually edges. Problems in implementing active contours such as convergence and initialization have motivated researchers to modify image forces of the active contours. This paper presents a comparative study among three different image forces: traditional snakes, balloon and gradient vector flow (GVF. The study is validated by experiments on abdominal image boundaries detection. These lead to the conclusion that GVF gives the most appropriate results among the other approaches.

  7. Fully automated contour detection algorithm the preliminary step for scatter and attenuation compensation in SPECT

    Energy Technology Data Exchange (ETDEWEB)

    Younes, R.B.; Mas, J.; Bidet, R.

    1988-12-01

    Contour detection is an important step in information extraction from nuclear medicine images. In order to perform accurate quantitative studies in single photon emission computed tomography (SPECT) a new procedure is described which can rapidly derive the best fit contour of an attenuated medium. Some authors evaluate the influence of the detected contour on the reconstructed images with various attenuation correction techniques. Most of the methods are strongly affected by inaccurately detected contours. This approach uses the Compton window to redetermine the convex contour: It seems to be simpler and more practical in clinical SPECT studies. The main advantages of this procedure are the high speed of computation, the accuracy of the contour found and the programme's automation. Results obtained using computer simulated and real phantoms or clinical studies demonstrate the reliability of the present algorithm.

  8. Joint Denoising / Compression of Image Contours via Shape Prior and Context Tree

    OpenAIRE

    Zheng, Amin; Cheung, Gene; Florencio, Dinei

    2017-01-01

    With the advent of depth sensing technologies, the extraction of object contours in images---a common and important pre-processing step for later higher-level computer vision tasks like object detection and human action recognition---has become easier. However, acquisition noise in captured depth images means that detected contours suffer from unavoidable errors. In this paper, we propose to jointly denoise and compress detected contours in an image for bandwidth-constrained transmission to a...

  9. Parallel development of contour integration and visual contrast sensitivity at low spatial frequencies

    DEFF Research Database (Denmark)

    Benedek, Krisztina; Janáky, Márta; Braunitzer, Gábor;

    2010-01-01

    and contour integration in 152 healthy volunteers aged between 5 and 30 years. The results revealed a significant maturation of contrast sensitivity at low spatial frequencies (0.5, 1.2, and 1.9 cycles/degree) and contour integration. The largest developmental step was observed for both contrast sensitivity...... and contour integration tasks when the 5-8-year olds were compared with the 9-11-year olds. There was a significant correlation between the development of low spatial frequency contrast sensitivity and contour integration. These results raise the possibility that the development of low spatial frequency...

  10. Active contours extension and similarity indicators for improved 3D segmentation of thyroid ultrasound images

    Science.gov (United States)

    Poudel, P.; Illanes, A.; Arens, C.; Hansen, C.; Friebe, M.

    2017-03-01

    Thyroid segmentation in tracked 2D ultrasound (US) using active contours has a low segmentation accuracy mainly due to the fact that smaller structures cannot be efficiently recognized and segmented. To address this issue, we propose a new similarity indicator with the main objective to provide information to the active contour algorithm concerning the regions that the active contour should continue to expand or should stop. First, a preprocessing step is carried out in order to attenuate the noise present in the US image and to increase its contrast, using histogram equalization and a median filter. In the second step, active contours are used to segment the thyroid in each 2D image of the dataset. After performing a first segmentation, two similarity indicators (ratio of mean square error, MSE and correlation between histograms) are computed at each contour point of the initial segmented thyroid between rectangles located inside and outside the obtained contour. A threshold is used on a final indicator computed from the other two indicators to find the probable regions for further segmentation using active contours. This process is repeated until no new segmentation region is identified. Finally, all the segmented thyroid images passed through a 3D reconstruction algorithm to obtain a 3D volume segmented thyroid. The results showed that including similarity indicators based on histogram equalization and MSE between inside and outside regions of the contour can help to segment difficult areas that active contours have problem to segment.

  11. Parallel development of contour integration and visual contrast sensitivity at low spatial frequencies

    DEFF Research Database (Denmark)

    Benedek, Krisztina; Janáky, Márta; Braunitzer, Gábor

    2010-01-01

    and contour integration in 152 healthy volunteers aged between 5 and 30 years. The results revealed a significant maturation of contrast sensitivity at low spatial frequencies (0.5, 1.2, and 1.9 cycles/degree) and contour integration. The largest developmental step was observed for both contrast sensitivity...... processing may affect attentional mechanisms, which may have an impact on early contour integration.......It has been suggested that visual contrast sensitivity and contour integration functions exhibit a late maturation during adolescence. However, the relationship between these functions has not been investigated. The aim of this study was to assess the development of visual contrast sensitivity...

  12. Region-based geometric active contour for classification using hyperspectral remote sensing images

    Science.gov (United States)

    Yan, Lin

    2011-12-01

    The high spectral resolution of hyperspectral imaging (HSI) systems greatly enhances the capabilities of discrimination, identification and quantification of objects of different materials from remote sensing images, but they also bring challenges to the processing and analysis of HSI data. One issue is the high computation cost and the curse of dimensionality associated with the high dimensions of HSI data. A second issue is how to effectively utilize the information including spectral and spatial information embedded in HSI data. Geometric Active Contour (GAC) is a widely used image segmentation method that utilizes the geometric information of objects within images. One category of GAC models, the region-based GAC models (RGAC), have good potential for remote sensing image processing because they use both spectral and geometry information in images are robust to initial contour placement. These models have been introduced to target extractions and classifications on remote sensing images. However, there are some restrictions on the applications of the RGAC models on remote sensing. First, the heavy involvement of iterative contour evolutions makes GAC applications time-consuming and inconvenient to use. Second, the current RGAC models must be based on a certain distance metric and the performance of RGAC classifiers are restricted by the performance of the employed distance metrics. According to the key features of the RGAC models analyzed in this dissertation, a classification framework is developed for remote sensing image classifications using the RGAC models. This framework allows the RGAC models to be combined with conventional pixel-based classifiers to promote them to spectral-spatial classifiers and also greatly reduces the iterations of contour evolutions. An extended Chan-Vese (ECV) model is proposed that is able to incorporate the widely used distance metrics in remote sensing image processing. A new type of RGAC model, the edge-oriented RGAC model

  13. Statistical region-based active contours with exponential family observations

    CERN Document Server

    Lecellier, François; Fadili, Jalal; Aubert, Gilles; Revenu, Marinette

    2008-01-01

    In this paper, we focus on statistical region-based active contour models where image features (e.g. intensity) are random variables whose distribution belongs to some parametric family (e.g. exponential) rather than confining ourselves to the special Gaussian case. Using shape derivation tools, our effort focuses on constructing a general expression for the derivative of the energy (with respect to a domain) and derive the corresponding evolution speed. A general result is stated within the framework of multi-parameter exponential family. More particularly, when using Maximum Likelihood estimators, the evolution speed has a closed-form expression that depends simply on the probability density function, while complicating additive terms appear when using other estimators, e.g. moments method. Experimental results on both synthesized and real images demonstrate the applicability of our approach.

  14. Equivalence of Two Contour Prescriptions in Superstring Perturbation Theory

    CERN Document Server

    Sen, Ashoke

    2016-01-01

    Conventional superstring perturbation theory based on the world-sheet approach gives divergent results for the S-matrix whenever the total center of mass energy of the incoming particles exceeds the threshold of production of any final state consistent with conservation laws. Two systematic approaches have been suggested for dealing with this difficulty. The first one involves deforming the integration cycles over the moduli space of punctured Riemann surfaces into complexified moduli space. The second one treats the amplitude as a sum of superstring field theory Feynman diagrams and deforms the integration contours over loop energies of the Feynman diagram into the complex plane. In this paper we establish the equivalence of the two prescriptions to all orders in perturbation theory. Since the second approach is known to lead to unitary amplitudes, this establishes the consistency of the first prescription with unitarity.

  15. Hough Transform and Active Contour for Enhanced Iris Segmentation

    Directory of Open Access Journals (Sweden)

    Alaa Hilal

    2012-11-01

    Full Text Available Iris segmentation is considered as the most difficult and fundamental step in an iris recognition system. While iris boundaries are largely approximated by two circles or ellipses, other methods define more accurately the iris resulting in better recognition results. In this paper we propose an iris segmentation method using Hough transform and active contour to detect a circular approximation of the outer iris boundary and to accurately segment the inner boundary in its real shape motivated by the fact that richer iris textures are closer to the pupil than to the sclera. Normalization, encoding and matching are implemented according to Daugmans method. The method, tested on CASIA-V3 iris images database is compared to Daugmans iris recognition system. Recognition performance is measured in terms of decidability, accuracy at the equal error rate and ROC curves. Improved recognition performance is obtained using our segmentation model proposing its use for better iris recognition system.

  16. Reconfigurable contour beam generation using a smart subreflector antenna system

    Science.gov (United States)

    Yoon, Hwan-Sik; Washington, Gregory N.; Theunissen, Wilhelmus H.

    2000-06-01

    A novel way to design, synthesize and adjust the reconfigurable dual offset contour beam reflector antenna employing an adjustable subreflector is presented. The work also presents a graphical user interface based computer code that connects the electro-magnetic effects to the mechanical surface deflections. The subreflector surface is described by using the finite element method and the far-field radiation pattern is calculated by reflector diffraction synthesis. The reflector surface shape is adjusted using a set of linear piezoelectric point actuators attached to its back surface, from which the diffraction synthesis code calculates the radiation pattern. An example of this method applied to the contiguous US is also presented. As a future work, a software package will be built where the finite element code and the diffraction synthesis code are combined, and it will be used for advanced actuator placement and reflector design problem.

  17. New method of 2-dimensional metrology using mask contouring

    Science.gov (United States)

    Matsuoka, Ryoichi; Yamagata, Yoshikazu; Sugiyama, Akiyuki; Toyoda, Yasutaka

    2008-10-01

    We have developed a new method of accurately profiling and measuring of a mask shape by utilizing a Mask CD-SEM. The method is intended to realize high accuracy, stability and reproducibility of the Mask CD-SEM adopting an edge detection algorithm as the key technology used in CD-SEM for high accuracy CD measurement. In comparison with a conventional image processing method for contour profiling, this edge detection method is possible to create the profiles with much higher accuracy which is comparable with CD-SEM for semiconductor device CD measurement. This method realizes two-dimensional metrology for refined pattern that had been difficult to measure conventionally by utilizing high precision contour profile. In this report, we will introduce the algorithm in general, the experimental results and the application in practice. As shrinkage of design rule for semiconductor device has further advanced, an aggressive OPC (Optical Proximity Correction) is indispensable in RET (Resolution Enhancement Technology). From the view point of DFM (Design for Manufacturability), a dramatic increase of data processing cost for advanced MDP (Mask Data Preparation) for instance and surge of mask making cost have become a big concern to the device manufacturers. This is to say, demands for quality is becoming strenuous because of enormous quantity of data growth with increasing of refined pattern on photo mask manufacture. In the result, massive amount of simulated error occurs on mask inspection that causes lengthening of mask production and inspection period, cost increasing, and long delivery time. In a sense, it is a trade-off between the high accuracy RET and the mask production cost, while it gives a significant impact on the semiconductor market centered around the mask business. To cope with the problem, we propose the best method of a DFM solution using two-dimensional metrology for refined pattern.

  18. Contours, Hawaii (Big Island) Hypsography - 40 ft Contour Interval, Published in 2004, 1:24000 (1in=2000ft) scale, U.S. Geological Survey.

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — This Contours dataset, published at 1:24000 (1in=2000ft) scale, was produced all or in part from Orthoimagery information as of 2004. It is described as 'Hawaii (Big...

  19. Bathymetric Contours - LAKE_BATHYMETRY_IDNR_IN: Bathymetric Contours for Selected Lakes in Indiana (Indiana Department of Natural Resources, Polygon Shapefile)

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — LAKE_BATHYMETRY_IDNR_IN.SHP provides bathymetric contours for the following 85 lakes in Indiana, with depths calculated from the average shoreline of each lake:...

  20. Contours, 2 and 5 foot contours, Published in 2007, 1:1200 (1in=100ft) scale, Mississippi Department of Environmental Quality.

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — This Contours dataset, published at 1:1200 (1in=100ft) scale, was produced all or in part from Field Observation information as of 2007. It is described as '2 and 5...

  1. Retroperitoneal Sarcoma Target Volume and Organ at Risk Contour Delineation Agreement Among NRG Sarcoma Radiation Oncologists

    Energy Technology Data Exchange (ETDEWEB)

    Baldini, Elizabeth H., E-mail: ebaldini@partners.org [Department of Radiation Oncology, Dana-Farber Cancer Institute, Brigham and Women' s Hospital, Boston, Massachusetts (United States); Abrams, Ross A. [Department of Radiation Oncology, Rush University Medical Center, Chicago, Illinois (United States); Bosch, Walter [Department of Radiation Oncology, Washington University, St. Louis, Missouri (United States); Roberge, David [Department of Radiation Oncology, Centre Hospitalier de l' Universite de Montreal, Montreal, Quebec (Canada); Haas, Rick L.M. [Department of Radiotherapy, Netherlands Cancer Institute, Amsterdam (Netherlands); Catton, Charles N. [Department of Radiation Oncology, Princess Margaret Cancer Centre, Toronto, Ontario (Canada); Indelicato, Daniel J. [Department of Radiation Oncology, University of Florida Medical Center, Jacksonville, Florida (United States); Olsen, Jeffrey R. [Department of Radiation Oncology, Washington University, St. Louis, Missouri (United States); Deville, Curtiland [Department of Radiation Oncology, University of Pennsylvania, Philadelphia, Pennsylvania (United States); Chen, Yen-Lin [Department of Radiation Oncology, Massachusetts General Hospital, Boston, Massachusetts (United States); Finkelstein, Steven E. [Translational Research Consortium, 21st Century Oncology, Scottsdale, Arizona (United States); DeLaney, Thomas F. [Department of Radiation Oncology, Massachusetts General Hospital, Boston, Massachusetts (United States); Wang, Dian [Department of Radiation Oncology, Rush University Medical Center, Chicago, Illinois (United States)

    2015-08-01

    Purpose: The purpose of this study was to evaluate the variability in target volume and organ at risk (OAR) contour delineation for retroperitoneal sarcoma (RPS) among 12 sarcoma radiation oncologists. Methods and Materials: Radiation planning computed tomography (CT) scans for 2 cases of RPS were distributed among 12 sarcoma radiation oncologists with instructions for contouring gross tumor volume (GTV), clinical target volume (CTV), high-risk CTV (HR CTV: area judged to be at high risk of resulting in positive margins after resection), and OARs: bowel bag, small bowel, colon, stomach, and duodenum. Analysis of contour agreement was performed using the simultaneous truth and performance level estimation (STAPLE) algorithm and kappa statistics. Results: Ten radiation oncologists contoured both RPS cases, 1 contoured only RPS1, and 1 contoured only RPS2 such that each case was contoured by 11 radiation oncologists. The first case (RPS 1) was a patient with a de-differentiated (DD) liposarcoma (LPS) with a predominant well-differentiated (WD) component, and the second case (RPS 2) was a patient with DD LPS made up almost entirely of a DD component. Contouring agreement for GTV and CTV contours was high. However, the agreement for HR CTVs was only moderate. For OARs, agreement for stomach, bowel bag, small bowel, and colon was high, but agreement for duodenum (distorted by tumor in one of these cases) was fair to moderate. Conclusions: For preoperative treatment of RPS, sarcoma radiation oncologists contoured GTV, CTV, and most OARs with a high level of agreement. HR CTV contours were more variable. Further clarification of this volume with the help of sarcoma surgical oncologists is necessary to reach consensus. More attention to delineation of the duodenum is also needed.

  2. Automatic diatom identification using contour analysis by morphological curvature scale spaces

    NARCIS (Netherlands)

    Jalba, Andrei C.; Wilkinson, Michael H.F.; Roerdink, Jos B.T.M.; Bayer, Micha M.; Juggins, Stephen

    2005-01-01

    A method for automatic identification of diatoms (single-celled algae with silica shells) based on extraction of features on the contour of the cells by multi-scale mathematical morphology is presented. After extracting the contour of the cell, it is smoothed adaptively, encoded using Freeman chain

  3. Contour Extraction in Prostate Ultrasound Images Using the Wavelet Transform and Snakes

    Science.gov (United States)

    2007-11-02

    signal noise levels. In this paper we present a semi-automatic prostate contour extraction scheme, which is based on the wavelet transform and active...contour models, or snakes. The ultrasound image is first decomposed into edge naps at different resolutions via the wavelet transform . Seed points are

  4. Hemagglutinin outer contour detection methods based on regular hexagon bar template

    Science.gov (United States)

    Tian, Miaomiao; Jing, Wenbo; Duan, Jin; Wang, Xiaoman

    2014-11-01

    In order to extract hemagglutinin outer contour accurately in the hemagglutinin image, analyzes the hemagglutinin protein content by the size of detected contour, presents a regular hexagon bar circle detection algorithm which uses regular hexagon bar detection template to detect outer contour of the hemagglutinin. Firstly, the hemagglutinin image thresholded by using OTSU adaptive thresholding method; and then using regular hexagon bar detection template method to rough align hemagglutinin after thresholded, intersection of detection template and the hemagglutinin contour area is attained, the noise near hemagglutinin contour is reduced by using the standardization relationship of the hexagon bars, so the hemagglutinin pixels are accurately obtained; finally the hemagglutinin outer contour information is gained by the geometric relationship of pixels, the hemagglutinin position is achieved precisely. The experimental results show that: the contour detection error due to the density uneven and the edge unclearly of hemagglutinin image protein is better reduced, the detection accuracy is increased by a factor of 0.47, detection speed is increased by a factor of 0.56.The hemagglutinin contour can be dected stablely, fastly, accurately and the is significant to the study of the hemagglutinin protein content.

  5. Patient-Reported Outcomes in Weight Loss and Body Contouring Surgery

    DEFF Research Database (Denmark)

    Poulsen, Lotte; Klassen, Anne; Rose, Michael

    2017-01-01

    to the post-body contouring surgery period. Data were collected using REDCap, and analyzed using SPSS software. RESULTS: For all appearance and health-related quality-of-life scales, the mean score was significantly lower in the pre-bariatric surgery group compared with the post-body contouring group...

  6. Dilated contour extraction and component labeling algorithm for object vector representation

    Science.gov (United States)

    Skourikhine, Alexei N.

    2005-08-01

    Object boundary extraction from binary images is important for many applications, e.g., image vectorization, automatic interpretation of images containing segmentation results, printed and handwritten documents and drawings, maps, and AutoCAD drawings. Efficient and reliable contour extraction is also important for pattern recognition due to its impact on shape-based object characterization and recognition. The presented contour tracing and component labeling algorithm produces dilated (sub-pixel) contours associated with corresponding regions. The algorithm has the following features: (1) it always produces non-intersecting, non-degenerate contours, including the case of one-pixel wide objects; (2) it associates the outer and inner (i.e., around hole) contours with the corresponding regions during the process of contour tracing in a single pass over the image; (3) it maintains desired connectivity of object regions as specified by 8-neighbor or 4-neighbor connectivity of adjacent pixels; (4) it avoids degenerate regions in both background and foreground; (5) it allows an easy augmentation that will provide information about the containment relations among regions; (6) it has a time complexity that is dominantly linear in the number of contour points. This early component labeling (contour-region association) enables subsequent efficient object-based processing of the image information.

  7. The Role of Tone Height, Melodic Contour, and Tone Chroma in Melody Recognition.

    Science.gov (United States)

    Massaro, Dominic W.; And Others

    1980-01-01

    Relationships among tone height, melodic contour, tone chroma, and recognition of recently learned melodies were investigated. Results replicated previous studies using familiar folk songs, providing evidence that melodic contour, tone chroma, and tone height contribute to recognition of both highly familiar and recently learned melodies.…

  8. Fourier Descriptor Analysis and Unification of Voice Range Profile Contours: Method and Applications

    Science.gov (United States)

    Pabon, Peter; Ternstrom, Sten; Lamarche, Anick

    2011-01-01

    Purpose: To describe a method for unified description, statistical modeling, and comparison of voice range profile (VRP) contours, even from diverse sources. Method: A morphologic modeling technique, which is based on Fourier descriptors (FDs), is applied to the VRP contour. The technique, which essentially involves resampling of the curve of the…

  9. Contour Propagation Using Feature-Based Deformable Registration for Lung Cancer

    Directory of Open Access Journals (Sweden)

    Yuhan Yang

    2013-01-01

    Full Text Available Accurate target delineation of CT image is a critical step in radiotherapy treatment planning. This paper describes a novel strategy for automatic contour propagation, based on deformable registration, for CT images of lung cancer. The proposed strategy starts with a manual-delineated contour in one slice of a 3D CT image. By means of feature-based deformable registration, the initial contour in other slices of the image can be propagated automatically, and then refined by active contour approach. Three algorithms are employed in the strategy: the Speeded-Up Robust Features (SURF, Thin-Plate Spline (TPS, and an adapted active contour (Snake, used to refine and modify the initial contours. Five pulmonary cancer cases with about 400 slices and 1000 contours have been used to verify the proposed strategy. Experiments demonstrate that the proposed strategy can improve the segmentation performance in the pulmonary CT images. Jaccard similarity (JS mean is about 0.88 and the maximum of Hausdorff distance (HD is about 90%. In addition, delineation time has been considerably reduced. The proposed feature-based deformable registration method in the automatic contour propagation improves the delineation efficiency significantly.

  10. Fourier Descriptor Analysis and Unification of Voice Range Profile Contours: Method and Applications

    Science.gov (United States)

    Pabon, Peter; Ternstrom, Sten; Lamarche, Anick

    2011-01-01

    Purpose: To describe a method for unified description, statistical modeling, and comparison of voice range profile (VRP) contours, even from diverse sources. Method: A morphologic modeling technique, which is based on Fourier descriptors (FDs), is applied to the VRP contour. The technique, which essentially involves resampling of the curve of the…

  11. Post-bariatric surgery body contouring treatment in the public health system: cost study and perception by patients.

    Science.gov (United States)

    Vilà, Jordi; Balibrea, José María; Oller, Benjamí; Alastrué, Antonio; Poyatos, Jordi Vilà; Balibrea del Castillo, José María; Sales, Benjamí Oller; Vidal, Antonio Alastrué

    2014-09-01

    Post-bariatric, body contouring surgery to treat the sequelae of massive weight loss is an undervalued topic by patients and in most of the literature. The objective of this study was to determine the mean cost per patient of this treatment in a public morbid obesity unit, and compare it with the perception by the patients. Costs were estimated using a specific Diagnosis-Related Group-based method and a questionnaire in a sample of 100 patients who had completed body contouring treatment. This study included 23 men and 77 women with a mean age of 48.5 years, a mean reduction of body mass index of 20.77 kg/m, and a median follow-up of 58 months. These patients had undergone surgery, as needed, as follows: on the lower part of the trunk (109 operations; mean cost, &OV0556;6348.6), cruroplasty (43 operations; mean cost, &OV0556;3490), brachioplasty (28 operations; mean cost &OV0556;3150), and the upper part of the trunk (10 operations; mean cost, &OV0556;4290). The rate of complications has been high (up to 50 percent) and, although the more severe complications are rare (10.5 percent Clavien grade IIIb), these represent high costs (mean, &OV0556;24462.6). Forty-five patients answered the questionnaire. Although they think that this surgery improves their quality of life, they have undervalued its total cost (17.58 percent; &OV0556;2034) (p = 0.16). The average cost of post-bariatric surgery body contouring treatment in this unit is &OV0556;8263.95 (1.66 operations per patient). The severe complications increase by 2.96 times the average cost per patient.

  12. Explicit calculation of multi-fold contour integrals of certain ratios of Euler gamma functions. Pt. 1

    Energy Technology Data Exchange (ETDEWEB)

    Gonzalez, Ivan [Valparaiso Univ. (Chile). Inst. de Fisica y Astronomia; Kniehl, Bernd A. [Hamburg Univ. (Germany). II. Inst. fuer Theoretische Physik; Kondrashuk, Igor [Univ. del Bio-Bio, Chillan (Chile). Dept. de Ciencias Basicas; Notte-Cuello, Eduardo A. [La Serena Univ. (Chile). Dept. de Matematicas; Parra-Ferrada, Ivan [Talca Univ. (Chile). Inst. de Matematica y Fisica; Rojas-Medar, Marko A. [Univ. de Tarapaca, Arica (Chile). Inst. de Alta Investigacion

    2016-12-15

    In this paper we proceed to study properties of Mellin-Barnes (MB) transforms of Usyukina-Davydychev (UD) functions. In our previous papers [Nuclear Physics B 870 (2013) 243], [Nuclear Physics B 876 (2013) 322] we showed that multi-fold Mellin-Barnes (MB) transforms of Usyukina-Davydychev (UD) functions may be reduced to two-fold MB transforms and that the higher-order UD functions were obtained in terms of a differential operator by applying it to a slightly modified first UD function. The result is valid in d=4 dimensions and its analog in d=4-2ε dimensions exits too [Theoretical and Mathematical Physics 177 (2013) 1515]. In [Nuclear Physics B 870 (2013) 243] the chain of recurrent relations for analytically regularized UD functions was obtained implicitly by comparing the left hand side and the right hand side of the diagrammatic relations between the diagrams with different loop orders. In turn, these diagrammatic relations were obtained due to the method of loop reductions for the triangle ladder diagrams proposed in 1983 by Belokurov and Usyukina. Here we reproduce these recurrent relations by calculating explicitly via Barnes lemmas the contour integrals produced by the left hand sides of the diagrammatic relations. In such a way we explicitly calculate a family of multi-fold contour integrals of certain ratios of Euler gamma functions. We make a conjecture that similar results for the contour integrals are valid for a wider family of smooth functions which includes the MB transforms of UD functions.

  13. Coronal loop detection and salient contour group extraction from solar images

    Science.gov (United States)

    Durak, Nurcan

    2011-01-01

    This dissertation addresses two different problems: 1) coronal loop detection from solar images: and 2) salient contour group extraction from cluttered images. In the first part, we propose two different solutions to the coronal loop detection problem. The first solution is a block-based coronal loop mining method that detects coronal loops from solar images by dividing the solar image into fixed sized blocks, labeling the blocks as "Loop" or "Non-Loop", extracting features from the labeled blocks, and finally training classifiers to generate learning models that can classify new image blocks. The block-based approach achieves 64% accuracy in 10-fold cross validation experiments. To improve the accuracy and scalability, we propose a contour-based coronal loop detection method that extracts contours from cluttered regions, then labels the contours as "Loop" and "Non-Loop", and extracts geometric features from the labeled contours. The contour-based approach achieves 85% accuracy in 10-fold cross validation experiments, which is a 20% increase compared to the block-based approach. In the second part, we propose a method to extract semi-elliptical open curves from cluttered regions. Our method consists of the following steps: obtaining individual smooth contours along with their saliency measures; then starting from the most salient contour, searching for possible grouping options for each contour; and continuing the grouping until an optimum solution is reached. Our work involved the design and development of a complete system for coronal loop mining in solar images, which required the formulation of new Gestalt perceptual rules and a systematic methodology to select and combine them in a fully automated judicious manner using machine learning techniques that eliminate the need to manually set various weight and threshold values to define an effective cost function. After finding salient contour groups, we close the gaps within the contours in each group and perform

  14. Optical contouring of an acrylic surface for non-intrusive diagnostics in pipe-flow investigations

    Science.gov (United States)

    de Witt, Benjamin J.; Coronado-Diaz, Haydee; Hugo, Ronald J.

    2008-07-01

    In this work, an acrylic surface was optically contoured to correct for the optical distortion caused by a transparent pipe wall. This method can be applied to non-invasive viewing/imaging techniques for fluid flow experiments. Software tools were developed to aid in the design of an optically contoured acrylic test section for pipe-flow experiments. Numerical models were computed for a standard acrylic pipe, inner diameter 57.15 mm, with water enclosed. An optical contour prototype was machined on a 5-axis CNC machine, and polished with 1-15 μm diamond paste, alleviating any surface imperfections without significantly altering the contoured surface. Experiments were then performed to measure the emerging optical wavefront and was found to emerge planar when utilizing the optical contour. It was determined that the wavefront was corrected to within ten wavelengths of a Helium-Neon (He-Ne) laser beam.

  15. Parallel algorithm for real-time contouring from grid DEM on modern GPUs

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    A real-time algorithm for constructing contour maps from grid DEM data is pre-sented.It runs completely within the programmable 3D visualization pipeline.The interpolation is paralleled by rasterizer units in the graphics card,and contour line extraction is paralleled by pixel shader.During each frame of the rendering,we first make an elevation gradient map out of original terrain vertex data,then figure out the final contour lines with image-space processing,and directly blend the results on the original scene to obtain a final scene with contour map using alpha-blending.We implement this method in our global 3D-digitalearth system with Direct3D?9.0c API and tested on some consumer level PC platforms.For arbitrary scene with certain LOD level,the process takes less than 10 ms,giving topologically correct,anti-aliased contour lines.

  16. Expert Consensus Contouring Guidelines for Intensity Modulated Radiation Therapy in Esophageal and Gastroesophageal Junction Cancer

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Abraham J., E-mail: wua@mskcc.org [Memorial Sloan-Kettering Cancer Center, New York, New York (United States); Bosch, Walter R. [Washington University, St. Louis, Missouri (United States); Chang, Daniel T. [Stanford Cancer Institute, Stanford, California (United States); Hong, Theodore S. [Massachusetts General Hospital, Boston, Massachusetts (United States); Jabbour, Salma K. [Rutgers Cancer Institute of New Jersey, New Brunswick, New Jersey (United States); Kleinberg, Lawrence R. [Johns Hopkins Medical Center, Baltimore, Maryland (United States); Mamon, Harvey J. [Brigham and Women' s Hospital, Boston, Massachusetts (United States); Thomas, Charles R. [Knight Cancer Institute, Oregon Health & Sciences University, Portland, Oregon (United States); Goodman, Karyn A. [Memorial Sloan-Kettering Cancer Center, New York, New York (United States)

    2015-07-15

    Purpose/Objective(s): Current guidelines for esophageal cancer contouring are derived from traditional 2-dimensional fields based on bony landmarks, and they do not provide sufficient anatomic detail to ensure consistent contouring for more conformal radiation therapy techniques such as intensity modulated radiation therapy (IMRT). Therefore, we convened an expert panel with the specific aim to derive contouring guidelines and generate an atlas for the clinical target volume (CTV) in esophageal or gastroesophageal junction (GEJ) cancer. Methods and Materials: Eight expert academically based gastrointestinal radiation oncologists participated. Three sample cases were chosen: a GEJ cancer, a distal esophageal cancer, and a mid-upper esophageal cancer. Uniform computed tomographic (CT) simulation datasets and accompanying diagnostic positron emission tomographic/CT images were distributed to each expert, and the expert was instructed to generate gross tumor volume (GTV) and CTV contours for each case. All contours were aggregated and subjected to quantitative analysis to assess the degree of concordance between experts and to generate draft consensus contours. The panel then refined these contours to generate the contouring atlas. Results: The κ statistics indicated substantial agreement between panelists for each of the 3 test cases. A consensus CTV atlas was generated for the 3 test cases, each representing common anatomic presentations of esophageal cancer. The panel agreed on guidelines and principles to facilitate the generalizability of the atlas to individual cases. Conclusions: This expert panel successfully reached agreement on contouring guidelines for esophageal and GEJ IMRT and generated a reference CTV atlas. This atlas will serve as a reference for IMRT contours for clinical practice and prospective trial design. Subsequent patterns of failure analyses of clinical datasets using these guidelines may require modification in the future.

  17. Expert consensus contouring guidelines for IMRT in esophageal and gastroesophageal junction cancer

    Science.gov (United States)

    Wu, Abraham J.; Bosch, Walter R.; Chang, Daniel T.; Hong, Theodore S.; Jabbour, Salma K.; Kleinberg, Lawrence R.; Mamon, Harvey J.; Thomas, Charles R.; Goodman, Karyn A.

    2015-01-01

    Purpose/Objective(s) Current guidelines for esophageal cancer contouring are derived from traditional two-dimensional fields based on bony landmarks, and do not provide sufficient anatomical detail to ensure consistent contouring for more conformal radiotherapy techniques such as intensity-modulated radiation therapy (IMRT). Therefore, we convened an expert panel with the specific aim to derive contouring guidelines and generate an atlas for the clinical target volume (CTV) in esophageal or gastroesophageal junction (GEJ) cancer. Methods and Materials Eight expert academically-based gastrointestinal radiation oncologists participated. Three sample cases were chosen: a GEJ cancer, a distal esophageal cancer, and a mid-upper esophageal cancer. Uniform CT simulation datasets and an accompanying diagnostic PET-CT were distributed to each expert, and he/she was instructed to generate gross tumor volume (GTV) and CTV contours for each case. All contours were aggregated and subjected to quantitative analysis to assess the degree of concordance between experts and generate draft consensus contours. The panel then refined these contours to generate the contouring atlas. Results Kappa statistics indicated substantial agreement between panelists for each of the three test cases. A consensus CTV atlas was generated for the three test cases, each representing common anatomic presentations of esophageal cancer. The panel agreed on guidelines and principles to facilitate the generalizability of the atlas to individual cases. Conclusions This expert panel successfully reached agreement on contouring guidelines for esophageal and GEJ IMRT and generated a reference CTV atlas. This atlas will serve as a reference for IMRT contours for clinical practice and prospective trial design. Subsequent patterns of failure analyses of clinical datasets utilizing these guidelines may require modification in the future. PMID:26104943

  18. An evaluation of the contouring abilities of medical dosimetry students for the anatomy of a prostate cancer patient

    Energy Technology Data Exchange (ETDEWEB)

    Collins, Kevin S., E-mail: kscollin@siu.edu [School of Allied Health, College of Applied Sciences and Arts, Southern Illinois University Carbondale, Carbondale, IL (United States)

    2012-10-01

    Prostate cancer is one of the most common diseases treated in a radiation oncology department. One of the major predictors of the treatment outcome and patient side effects is the accuracy of the anatomical contours for the treatment plan. Therefore, the purpose of this study was to determine which anatomical structures are most often contoured correctly and incorrectly by medical dosimetry students. The author also wanted to discover whether a review of the contouring rules would increase contouring accuracy. To achieve this, a male computed tomography dataset consisting of 72 transverse slices was sent to students for contouring. The students were instructed to import this dataset into their treatment planning system and contour the following structures: skin, bladder, rectum, prostate, penile bulb, seminal vesicles, left femoral head, and right femoral head. Upon completion of the contours, the contour file was evaluated against a 'gold standard' contour set using StructSure software (Standard Imaging, Inc). A review of the initial contour results was conducted and then students were instructed to contour the dataset a second time. The results of this study showed significant differences between contouring sessions. These results and the standardization of contouring rules should benefit all individuals who participate in the treatment planning of cancer patients.

  19. Contours, 2 foot contours from LiDAR flown under the LAR-IAC project, Published in 2006, 1:600 (1in=50ft) scale, County of Los Angeles.

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — This Contours dataset, published at 1:600 (1in=50ft) scale, was produced all or in part from LIDAR information as of 2006. It is described as '2 foot contours from...

  20. Contours, Contours created by processing hillshade TIF files derived from the U.S. Geological Survey National Elevation Dataset. Available in 50',100, 250', and 500' intervals., Published in 2004, Arizona State Land Department.

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — This Contours dataset as of 2004. It is described as 'Contours created by processing hillshade TIF files derived from the U.S. Geological Survey National Elevation...

  1. Contours, 2' contours do not cover the entire county, although most of the Green Bay Metro area and villages are complete, Published in 2000, 1:2400 (1in=200ft) scale, Brown County, WI.

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — This Contours dataset, published at 1:2400 (1in=200ft) scale, was produced all or in part from Orthoimagery information as of 2000. It is described as '2' contours...

  2. Contours, Elevation contour data are a fundamental base map layer for large scale mapping and GIS analysis., Published in 2001, 1:24000 (1in=2000ft) scale, Louisiana State University.

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — This Contours dataset, published at 1:24000 (1in=2000ft) scale as of 2001. It is described as 'Elevation contour data are a fundamental base map layer for large...

  3. 改进的RSA算法在数字签名中的应用%Improved RSA algorithm and application in digital signature

    Institute of Scientific and Technical Information of China (English)

    肖振久; 胡驰; 陈虹

    2014-01-01

    In order to enhance the operation efficiency of RSA algorithm, a new improved algorithm is suggested in this paper which makes some improvements in structure and operation, and it is applied to digital signature. The experiment makes comparison between a combinatorial optimization algorithm which combines SMM with index of 2k hexadecimal algorithm and the new algorithm. It shows that the new algorithm reaches a high level in operation speed.%针对传统RSA密码算法运算效率较低的问题,在标准RSA密码算法的自身结构和具体运算操作两方面做出了相应的改进,提出了一种新的RSA密码优化算法,并将该算法运用到数字签名技术中。然后通过仿真实验,将其与传统RSA算法以及基于乘同余对称特性的SMM算法和指数2k进制化相结合的组合优化算法相比较,实验结果表明新的RSA密码优化算法在提升运算速度方面达到了较高的水平。

  4. 基于RSA的叛逆者追踪方案的设计与分析%The Analysis and Design of Traitor Tracing Scheme Based on RSA

    Institute of Scientific and Technical Information of China (English)

    齐亚莉

    2012-01-01

    叛逆者追踪方案是版权保护中的重要工具。基于RSA算法的安全性,设计叛逆者追踪方案,数据分发者分别为每个用户进行初始化,使每个用户都具有标志性的用户信息,可准确地追踪到叛逆者。对方案进行分析后得出结论:为保证安全性,需要不断增加密钥长度,但其不可否认性和防诬陷性使该追踪算法的应用受到一定限制。%Traitor tracing technology is an important measure to data copyright protection. This paper designs a traitor tracing scheme based on RSA, which dispatches special information for every users respectively. The information for one user is the label of him. The scheme has the advantages of tracing traitor and revoking traitor successfully. But it is restrained by non-re- pudiation and full frameproof to application.

  5. Computational study of a contoured plug-nozzle as a supersonic jet noise suppressor

    Science.gov (United States)

    Khavaran, A.; Das, A. P.; Das, I.S.

    1996-01-01

    The report summarizes a computational jet noise study of an ideal contoured plug-nozzle (CPN). The gasdynamics of the jet flows have been predicted using the CFD code, NPARC with k-epsilon turbulence model; these data are then used as inputs to perform the noise computations based on the modified version of General Electric MGB code. The study covers a range of operating pressure ratio, 2.0 less than xi less than 5.0 (shockless flow at design pressure ratio, xi(d) = 3.62). The agreement of the computational aeroacoustics results with the available experimental data may be considered to be favorable. The computational results indicate consistent noise reduction effectiveness of the CPN at all operating pressure ratios. At the design pressure ratio (shockless), the codes predict overall sound pressure levels within +3.O dB of the experimental data. But at the off-design pressure ratios (flaws with shocks), the agreement is rather mixed. The theory overpredicts the OASPL's at all pressure ratios except at lower angles to the jet axis in overexpanded mode (xi less than xi(d)), the deviations being within 4.5 dB. The mechanism of shock formations in the CPN jet flows is noted to be basically different from those in the convergent-divergent nozzle jet flows.

  6. Reliability and validity of resilience scale for adults(RSA) in military students%成人心理弹性量表在军校大学生中的信效度研究

    Institute of Scientific and Technical Information of China (English)

    张佳佳; 任景敏; 黄健; 李敏; 魏琳; 张钰; 李培培; 张丽丽; 汪涛

    2010-01-01

    目的 研究成人心理弹性量表(RSA)在军校大学生中的信效度.方法 采用成人心理弹性量表(RSA)和症状自评量表(SCL-90)中的抑郁、焦虑、躯体化3个因子对某军校616名学生进行整群抽样调查.结果 ①对RSA采用探索性因素分析.共提取5个因子.各项目在因子上的负荷在0.423~0.834之间,累计方差解释率为58.439%;②RSA各因子之间相关显著.相关系数在0.228~0.580之间;各因子与总分相关显著,相关系数在0.565~0.789之间;③效标SCL-90的抑郁、焦虑和躯体化三个因子的均分与RSA均分之间呈显著负相关,相关系数为-0.437(n=593,P=0.000);④RSA各个因子的同质性信度在0.52~0.86之间,RSA问卷信度为0.91.结论 RSA量表在军校学生中信效度较好.%Objective To research the reliability and validity of resilience scale for adults(RSA)in military students.Methods RSA, depression, anxiety and somatization of Self-report Symptom Checklist 90(SCL-90)were applied in this survey to 616 military students.Results ①A 5-factor structure of resilience was showed by explorative factor analysis.Each item had a factor loading between 0.423~0.834, and the total variance explained at 58.439%.②The correlations between the subscales of the RSA were all obvious positive, ranging from 0.228~0.580;and the correlations between subscales of the RSA and total resilience were all obvious positive, ranging from 0.565~0.789.③There was a obvious negative correlation between total depression, anxiety and somatization and total resilience, the correlation coefficient was-0.437(n=593, P=0.000).④Tbe reliability coefficient of the RSA was 0.91, and the respective dimensions had Cronbach's alphas between 0.52~0.86.Conclusion The results show that RSA has acceptable reliability and validity in military students.

  7. Statistical Modeling Approach to Quantitative Analysis of Interobserver Variability in Breast Contouring

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Jinzhong, E-mail: jyang4@mdanderson.org [Department of Radiation Physics, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Woodward, Wendy A.; Reed, Valerie K.; Strom, Eric A.; Perkins, George H.; Tereffe, Welela; Buchholz, Thomas A. [Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Zhang, Lifei; Balter, Peter; Court, Laurence E. [Department of Radiation Physics, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Li, X. Allen [Department of Radiation Oncology, Medical College of Wisconsin, Milwaukee, Wisconsin (United States); Dong, Lei [Department of Radiation Physics, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Scripps Proton Therapy Center, San Diego, California (United States)

    2014-05-01

    Purpose: To develop a new approach for interobserver variability analysis. Methods and Materials: Eight radiation oncologists specializing in breast cancer radiation therapy delineated a patient's left breast “from scratch” and from a template that was generated using deformable image registration. Three of the radiation oncologists had previously received training in Radiation Therapy Oncology Group consensus contouring for breast cancer atlas. The simultaneous truth and performance level estimation algorithm was applied to the 8 contours delineated “from scratch” to produce a group consensus contour. Individual Jaccard scores were fitted to a beta distribution model. We also applied this analysis to 2 or more patients, which were contoured by 9 breast radiation oncologists from 8 institutions. Results: The beta distribution model had a mean of 86.2%, standard deviation (SD) of ±5.9%, a skewness of −0.7, and excess kurtosis of 0.55, exemplifying broad interobserver variability. The 3 RTOG-trained physicians had higher agreement scores than average, indicating that their contours were close to the group consensus contour. One physician had high sensitivity but lower specificity than the others, which implies that this physician tended to contour a structure larger than those of the others. Two other physicians had low sensitivity but specificity similar to the others, which implies that they tended to contour a structure smaller than the others. With this information, they could adjust their contouring practice to be more consistent with others if desired. When contouring from the template, the beta distribution model had a mean of 92.3%, SD ± 3.4%, skewness of −0.79, and excess kurtosis of 0.83, which indicated a much better consistency among individual contours. Similar results were obtained for the analysis of 2 additional patients. Conclusions: The proposed statistical approach was able to measure interobserver variability quantitatively

  8. RSA加密算法的有效实现及在云计算中的应用%Analysis to Effective Realization of RSA Encryption Algorithm and Its Application in the Cloud Computing

    Institute of Scientific and Technical Information of China (English)

    谢会娟; 韩昌豪; 吴明珠

    2014-01-01

    随着互联网的发展,云计算模式能够提供便捷的、可用的和按需要网络资源,云计算的核心是如何存储和管理用户的数据,除了配置存储设备的之外,还要考虑到存储在云中的数据的安全性。RSA加密算法是基于一个比较简单的数论-两个大素数相乘十分容易实现,但要对它的乘积进行因式分解却十分困难,RSA加密算法是将乘积公开作为加密密钥的非对称加密方法,在云计算中应用RSA算法对存储在云中的数据进行加密,能够保证了数据的安全性。%With the development of the Internet, cloud computing can provide convenient and available network resources, the core of cloud computing is how to store and manage user data, cloud computing does not provide storage devices, but also takes into account the security of the data stored in the cloud. RSA encryption algorithm is based on a relatively simple theory of math-multiplying two large prime numbers is very easy to achieve, but it's the factorization is very difficult, RSA encryption al⁃gorithm considers a product as a public encryption key and is an asymmetric encryption method. To ensure the security of the da⁃ta, RSA encryption algorithm is applied for the data storage in the cloud.

  9. A review: aluminum nitride MEMS contour-mode resonator

    Science.gov (United States)

    Yunhong, Hou; Meng, Zhang; Guowei, Han; Chaowei, Si; Yongmei, Zhao; Jin, Ning

    2016-10-01

    Over the past several decades, the technology of micro-electromechanical system (MEMS) has advanced. A clear need of miniaturization and integration of electronics components has had new solutions for the next generation of wireless communications. The aluminum nitride (AlN) MEMS contour-mode resonator (CMR) has emerged and become promising and competitive due to the advantages of the small size, high quality factor and frequency, low resistance, compatibility with integrated circuit (IC) technology, and the ability of integrating multi-frequency devices on a single chip. In this article, a comprehensive review of AlN MEMS CMR technology will be presented, including its basic working principle, main structures, fabrication processes, and methods of performance optimization. Among these, the deposition and etching process of the AlN film will be specially emphasized and recent advances in various performance optimization methods of the CMR will be given through specific examples which are mainly focused on temperature compensation and reducing anchor losses. This review will conclude with an assessment of the challenges and future trends of the CMR. Project supported by National Natural Science Foundation (Nos. 61274001, 61234007, 61504130), the Nurturing and Development Special Projects of Beijing Science and Technology Innovation Base's Financial Support (No. Z131103002813070), and the National Defense Science and Technology Innovation Fund of CAS (No. CXJJ-14-M32).

  10. Multiplatform GPGPU implementation of the active contours without edges algorithm

    Science.gov (United States)

    Zavala-Romero, Olmo; Meyer-Baese, Anke; Meyer-Baese, Uwe

    2012-05-01

    An OpenCL implementation of the Active Contours Without Edges algorithm is presented. The proposed algorithm uses the General Purpose Computing on Graphics Processing Units (GPGPU) to accelerate the original model by parallelizing the two main steps of the segmentation process, the computation of the Signed Distance Function (SDF) and the evolution of the segmented curve. The proposed scheme for the computation of the SDF is based on the iterative construction of partial Voronoi diagrams of a reduced dimension and obtains the exact Euclidean distance in a time of order O(N/p), where N is the number of pixels and p the number of processors. With high resolution images the segmentation algorithm runs 10 times faster than its equivalent sequential implementation. This work is being done as an open source software that, being programmed in OpenCL, can be used in dierent platforms allowing a broad number of nal users and can be applied in dierent areas of computer vision, like medical imaging, tracking, robotics, etc. This work uses OpenGL to visualize the algorithm results in real time.

  11. Patterns in biofilms: From contour undulations to fold focussing

    Science.gov (United States)

    Ben Amar, Martine; Wu, Min

    2014-11-01

    Morphologies of soft materials in growth, swelling or drying have been extensively studied recently. Shape modifications occur as the size varies transforming ordinary spheres, cylinders and thin plates into more or less complex objects. Here we consider the genesis of biofilm patterns when a simple disc containing initially bacteria with moderate adhesion to a rigid substrate grows according to very simple rules. The initial circular geometry is lost during the growth expansion, contour undulations and buckling appear, ultimately a rather regular periodic focussing of folds repartition emerges. We theoretically predict these morphological instabilities as bifurcations of solutions in elasticity, characterized by typical driving parameters established here. The substrate plays a critical role limiting the geometry of the possible modes of instabilities and anisotropic growth, adhesion and toughness compete to eventually give rise to wrinkling, buckling or both. Additionally, due to the substrate, we show that the ordinary buckling modes, vertical deviation of thin films, are not observed in practice and a competitive pattern with self-focussing of folds can be found analytically. These patterns are reminiscent of the blisters of delamination in material sciences and explain recent observations of bacteria biofilms. The model presented here is purely analytical, is based on a neo-Hookean elastic energy, and can be extended without difficulties and applied to polymer materials.

  12. Contour Detection of Leukocyte Cell Nucleus Using Morphological Image

    Science.gov (United States)

    Supriyanti, R.; Satrio, G. P.; Ramadhani, Y.; Siswandari, W.

    2017-04-01

    Leukocytes are blood cells that do not contain color pigments. Leukocyte function to the tool body’s defenses. Abnormal forms of leukocytes can be a sign of serious diseases such example is leukemia. Most laboratories still use cell morphology examination to assist the diagnosis of illness associated with white blood cells such example is leukemia because of limited resources, both infrastructure, and human resources as happens in developing nations, such as Indonesia. This examination is less expensive and quicker process. However, morphological review requires the expertise of a specialist clinical pathology were limited. This process is sometimes less valid cause in some cases trying to differentiate morphology blast cells into the type of myoblasts, lymphoblast, monoblast, or erythroblast thus potentially misdiagnosis. The goal of this research is to develop a detection device types of blood cells automatically as lower-priced, easy to use and accurate so that the tool can be distributed across all units in existing health services throughout Indonesia and in particular for remote areas. However, because the variables used in the identification of abnormal leukocytes are very complex, in this paper, we emphasize on the contour detection of leukocyte cell nucleus using the morphological image. The results show that this method is promising for further development.

  13. Poverty Reduction

    OpenAIRE

    Ortiz, Isabel

    2007-01-01

    The paper reviews poverty trends and measurements, poverty reduction in historical perspective, the poverty-inequality-growth debate, national poverty reduction strategies, criticisms of the agenda and the need for redistribution, international policies for poverty reduction, and ultimately understanding poverty at a global scale. It belongs to a series of backgrounders developed at Joseph Stiglitz's Initiative for Policy Dialogue.

  14. Dominant point detecting based non-uniform B-spline approximation for grain contour

    Institute of Scientific and Technical Information of China (English)

    ZHAO XiuYang; YIN YanSheng; YANG Bo

    2007-01-01

    Three-dimension reconstruction from serial sections has been used in the last decade to obtain information concerning three-dimensional microstructural geometry. One of the crucial steps of three-dimension reconstruction is getting compact and fairing grain contours. Based on the achievement of closed raw contours of ceramic composite grains by using wavelet and level set, an adaptive method is adopted for the polygonal approximation of the digitized raw contours. Instead of setting a fixed length of support region in advance, the novel method computes the suitable length of support region for each point to find the best estimated curvature. The dominant points are identified as the points with local maximum estimated curvatures. Periodic closed B-spline approximation is used to find the most compact B-spline grain boundary contours within the given tolerance. A flexible distance selection approach is adopted to obtain the common knot vector of serial contours consisting of less knots that contain enough degrees of freedom to guarantee the existence of a B-spline curve interpolating each contour. Finally, a B-spline surface interpolating the serial contours is generated via B-spline surface skinning.

  15. Dominant point detecting based non-uniform B-spline approximation for grain contour

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Three-dimension reconstruction from serial sections has been used in the last decade to obtain information concerning three-dimensional microstructural ge-ometry. One of the crucial steps of three-dimension reconstruction is getting compact and fairing grain contours. Based on the achievement of closed raw con-tours of ceramic composite grains by using wavelet and level set, an adaptive method is adopted for the polygonal approximation of the digitized raw contours. Instead of setting a fixed length of support region in advance, the novel method computes the suitable length of support region for each point to find the best es-timated curvature. The dominant points are identified as the points with local maximum estimated curvatures. Periodic closed B-spline approximation is used to find the most compact B-spline grain boundary contours within the given tolerance. A flexible distance selection approach is adopted to obtain the common knot vector of serial contours consisting of less knots that contain enough degrees of freedom to guarantee the existence of a B-spline curve interpolating each contour. Finally, a B-spline surface interpolating the serial contours is generated via B-spline surface skinning.

  16. A shape-based inter-layer contours correspondence method for ICT-based reverse engineering.

    Science.gov (United States)

    Duan, Liming; Yang, Shangpeng; Zhang, Gui; Feng, Fei; Gu, Minghui

    2017-01-01

    The correspondence of a stack of planar contours in ICT (industrial computed tomography)-based reverse engineering, a key step in surface reconstruction, is difficult when the contours or topology of the object are complex. Given the regularity of industrial parts and similarity of the inter-layer contours, a specialized shape-based inter-layer contours correspondence method for ICT-based reverse engineering was presented to solve the above problem based on the vectorized contours. In this paper, the vectorized contours extracted from the slices consist of three graphical primitives: circles, arcs and segments. First, the correspondence of the inter-layer primitives is conducted based on the characteristics of the primitives. Second, based on the corresponded primitives, the inter-layer contours correspond with each other using the proximity rules and exhaustive search. The proposed method can make full use of the shape information to handle industrial parts with complex structures. The feasibility and superiority of this method have been demonstrated via the related experiments. This method can play an instructive role in practice and provide a reference for the related research.

  17. Performance of visual search tasks from various types of contour information.

    Science.gov (United States)

    Itan, Liron; Yitzhaky, Yitzhak

    2013-03-01

    A recently proposed visual aid for patients with a restricted visual field (tunnel vision) combines a see-through head-mounted display and a simultaneous minified contour view of the wide-field image of the environment. Such a widening of the effective visual field is helpful for tasks, such as visual search, mobility, and orientation. The sufficiency of image contours for performing everyday visual tasks is of major importance for this application, as well as for other applications, and for basic understanding of human vision. This research aims is to examine and compare the use of different types of automatically created contours, and contour representations, for practical everyday visual operations using commonly observed images. The visual operations include visual searching for items, such as cutlery, housewares, etc. Considering different recognition levels, identification of an object is distinguished from mere detection (when the object is not necessarily identified). Some nonconventional visual-based contour representations were developed for this purpose. Experiments were performed with normal-vision subjects by superposing contours of the wide field of the scene over a narrow field (see-through) background. From the results, it appears that about 85% success is obtained for searched object identification when the best contour versions are employed. Pilot experiments with video simulations are reported at the end of the paper.

  18. Prevalence and desire for body contouring surgery in postbariatric patients in Saudi Arabia

    Directory of Open Access Journals (Sweden)

    Saleh M Aldaqal

    2012-01-01

    Full Text Available Background: Morbid obesity has become a common problem worldwide and as a result the demand for bariatric surgery has increased as well. Most patients develop skin redundancy and sagging at many body parts after major weight loss procedures which increased the demand for body contouring procedures. Aims : The study was to address the prevalence and patient′s desire for body contouring procedures. Materials and Methods: A cross-sectional study targeting the postbariatric patients from April 2011 to October 2011 was conducted at our hospital. Questionnaire was administered in order to measure frequency and patients desire to undergo body contouring surgery after massive weight loss. Results: The total number of patients was 128 patients. The mean age of our patients was 37-year old (range 18-56 year. The percentage of the desire for body contouring surgery after bariatric surgery was 78.1%. There was very pronounced desire to body contouring surgery after those who underwent gastric bypass surgery with P-value 0.001. Only 18 patients (14% have underwent body contouring surgery, with a total of 29 procedures, in which abdominoplasty considered the most commonly procedure performed (57%. Conclusion : With the increasing number of weight loss surgery, there is higher number of patients that desire a body contouring surgery, which create huge disparity between demand and accessibility.

  19. Dynamic Maintenance of Half-Space Depth for Points and Contours

    CERN Document Server

    Burr, Michael A; Souvaine, Diane L

    2011-01-01

    Half-space depth (also called Tukey depth or location depth) is one of the most commonly studied data depth measures because it possesses many desirable properties for data depth functions. The data depth contours bound regions of increasing depth. For the sample case, there are two competing definitions of contours: the rank-based contours and the cover-based contours. In this paper, we present three dynamic algorithms for maintaining the half-space depth of points and contours: The first maintains the half-space depth of a single point in a data set in $O(\\log n)$ time per update (insertion/deletion) and overall linear space. By maintaining such a data structure for each data point, we present an algorithm for dynamically maintaining the rank-based contours in $O(n\\cdot\\log n)$ time per update and overall quadratic space. The third dynamic algorithm maintains the cover-based contours in $O(n\\cdot \\log^2 n)$ time per update and overall quadratic space. We also augment our first algorithm to maintain the loca...

  20. Brain MR image segmentation using local and global intensity fitting active contours/surfaces.

    Science.gov (United States)

    Wang, Li; Li, Chunming; Sun, Quansen; Xia, Deshen; Kao, Chiu-Yen

    2008-01-01

    In this paper, we present an improved region-based active contour/surface model for 2D/3D brain MR image segmentation. Our model combines the advantages of both local and global intensity information, which enable the model to cope with intensity inhomogeneity. We define an energy functional with a local intensity fitting term and an auxiliary global intensity fitting term. In the associated curve evolution, the motion of the contour is driven by a local intensity fitting force and a global intensity fitting force, induced by the local and global terms in the proposed energy functional, respectively. The influence of these two forces on the curve evolution is complementary. When the contour is close to object boundaries, the local intensity fitting force became dominant, which attracts the contour toward object boundaries and finally stops the contour there. The global intensity fitting force is dominant when the contour is far away from object boundaries, and it allows more flexible initialization of contours by using global image information. The proposed model has been applied to both 2D and 3D brain MR image segmentation with promising results.

  1. Contours, 2 foot contours automatically generated from 2008 LIDAR for the purpose of supporting FEMA floodplain mapping. Limited manual editing, breaklines for waterbodies greater than 5 acres created and use.10' index contours labeled., Published in 2008, 1:1200 (1in=100ft) scale, CITY OF PORTAGE.

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — This Contours dataset, published at 1:1200 (1in=100ft) scale, was produced all or in part from LIDAR information as of 2008. It is described as '2 foot contours...

  2. Pelvic Normal Tissue Contouring Guidelines for Radiation Therapy: A Radiation Therapy Oncology Group Consensus Panel Atlas

    Energy Technology Data Exchange (ETDEWEB)

    Gay, Hiram A., E-mail: hgay@radonc.wustl.edu [Washington University School of Medicine, St Louis, MO (United States); Barthold, H. Joseph [Commonwealth Hematology and Oncology, Weymouth, MA (United States); Beth Israel Deaconess Medical Center, Boston, MA (Israel); O' Meara, Elizabeth [Radiation Therapy Oncology Group, Philadelphia, PA (United States); Bosch, Walter R. [Washington University School of Medicine, St Louis, MO (United States); El Naqa, Issam [Department of Radiation Oncology, McGill University Health Center, Montreal, Quebec (Canada); Al-Lozi, Rawan [Washington University School of Medicine, St Louis, MO (United States); Rosenthal, Seth A. [Radiation Oncology Centers, Radiological Associates of Sacramento, Sacramento, CA (United States); Lawton, Colleen [Department of Radiation Oncology, Medical College of Wisconsin, Milwaukee, WI (United States); Lee, W. Robert [Department of Radiation Oncology, Duke University Medical Center, Durham, NC (United States); Sandler, Howard [Cedars-Sinai Medical Center, Los Angeles, CA (United States); Zietman, Anthony [Department of Radiation Oncology, Massachusetts General Hospital and Harvard Medical School, Boston, MA (United States); Myerson, Robert [Washington University School of Medicine, St Louis, MO (United States); Dawson, Laura A. [Department of Radiation Oncology, Princess Margaret Hospital, University of Toronto, Toronto, Ontario (Canada); Willett, Christopher [Department of Radiation Oncology, Duke University Medical Center, Durham, NC (United States); Kachnic, Lisa A. [Department of Radiation Oncology, Boston Medical Center, Boston University School of Medicine, Boston, MA (United States); Jhingran, Anuja [Department of Radiation Oncology, University of Texas MD Anderson Cancer Center, Houston, TX (United States); Portelance, Lorraine [University of Miami, Miami, FL (United States); Ryu, Janice [Radiation Oncology Centers, Radiological Associates of Sacramento, Sacramento, CA (United States); and others

    2012-07-01

    Purpose: To define a male and female pelvic normal tissue contouring atlas for Radiation Therapy Oncology Group (RTOG) trials. Methods and Materials: One male pelvis computed tomography (CT) data set and one female pelvis CT data set were shared via the Image-Guided Therapy QA Center. A total of 16 radiation oncologists participated. The following organs at risk were contoured in both CT sets: anus, anorectum, rectum (gastrointestinal and genitourinary definitions), bowel NOS (not otherwise specified), small bowel, large bowel, and proximal femurs. The following were contoured in the male set only: bladder, prostate, seminal vesicles, and penile bulb. The following were contoured in the female set only: uterus, cervix, and ovaries. A computer program used the binomial distribution to generate 95% group consensus contours. These contours and definitions were then reviewed by the group and modified. Results: The panel achieved consensus definitions for pelvic normal tissue contouring in RTOG trials with these standardized names: Rectum, AnoRectum, SmallBowel, Colon, BowelBag, Bladder, UteroCervix, Adnexa{sub R}, Adnexa{sub L}, Prostate, SeminalVesc, PenileBulb, Femur{sub R}, and Femur{sub L}. Two additional normal structures whose purpose is to serve as targets in anal and rectal cancer were defined: AnoRectumSig and Mesorectum. Detailed target volume contouring guidelines and images are discussed. Conclusions: Consensus guidelines for pelvic normal tissue contouring were reached and are available as a CT image atlas on the RTOG Web site. This will allow uniformity in defining normal tissues for clinical trials delivering pelvic radiation and will facilitate future normal tissue complication research.

  3. Variations in the Contouring of Organs at Risk: Test Case From a Patient With Oropharyngeal Cancer

    Energy Technology Data Exchange (ETDEWEB)

    Nelms, Benjamin E., E-mail: alpha@canislupusllc.com [Canis Lupus LLC, Merrimac, WI (United States); Tome, Wolfgang A. [Department of Human Oncology, University of Wisconsin, Madison, WI (United States); Robinson, Greg [Radiation Oncology Resources, Goshen, IN (United States); Wheeler, James [Department of Radiation Oncology, Goshen Health System Goshen, IN (United States)

    2012-01-01

    Purpose: Anatomy contouring is critical in radiation therapy. Inaccuracy and variation in defining critical volumes will affect everything downstream: treatment planning, dose-volume histogram analysis, and contour-based visual guidance used in image-guided radiation therapy. This study quantified: (1) variation in the contouring of organs at risk (OAR) in a clinical test case and (2) corresponding effects on dosimetric metrics of highly conformal plans. Methods and Materials: A common CT data set with predefined targets from a patient with oropharyngeal cancer was provided to a population of clinics, which were asked to (1) contour OARs and (2) design an intensity-modulated radiation therapy plan. Thirty-two acceptable plans were submitted as DICOM RT data sets, each generated by a different clinical team. Using those data sets, we quantified: (1) the OAR contouring variation and (2) the impact this variation has on dosimetric metrics. New technologies were employed, including a software tool to quantify three-dimensional structure comparisons. Results: There was significant interclinician variation in OAR contouring. The degree of variation is organ-dependent. We found substantial dose differences resulting strictly from contouring variation (differences ranging from -289% to 56% for mean OAR dose; -22% to 35% for maximum dose). However, there appears to be a threshold in the OAR comparison metric beyond which the dose differences stabilize. Conclusions: The effects of interclinician variation in contouring organs-at-risk in the head and neck can be large and are organ-specific. Physicians need to be aware of the effect that variation in OAR contouring can play on the final treatment plan and not restrict their focus only to the target volumes.

  4. Expansion/De-expansion Tool to Quantify the Accuracy of Prostate Contours

    Energy Technology Data Exchange (ETDEWEB)

    Chung, Eugene; Stenmark, Matthew H. [Department of Radiation Oncology, University of Michigan, Ann Arbor, MI (United States); Evans, Cheryl [Department of Radiation Oncology, Providence Cancer Center, Novi, MI (United States); Narayana, Vrinda [Department of Radiation Oncology, University of Michigan, Ann Arbor, MI (United States); Department of Radiation Oncology, Providence Cancer Center, Novi, MI (United States); McLaughlin, Patrick W., E-mail: mclaughb@med.umich.edu [Department of Radiation Oncology, University of Michigan, Ann Arbor, MI (United States); Department of Radiation Oncology, Providence Cancer Center, Novi, MI (United States)

    2012-05-01

    Purpose: Accurate delineation of the prostate gland on computed tomography (CT) remains a persistent challenge and continues to introduce geometric uncertainty into the planning and delivery of external beam radiotherapy. We, therefore, developed an expansion/de-expansion tool to quantify the contour errors and determine the location of the deviations. Methods and Materials: A planning CT scan and magnetic resonance imaging scan were prospectively acquired for 10 patients with prostate cancer. The prostate glands were contoured by 3 independent observers using the CT data sets with instructions to contour the prostate without underestimation but to minimize overestimation. The standard prostate for each patient was defined using magnetic resonance imaging and CT on multiple planes. After registration of the CT and magnetic resonance imaging data sets, the CT-defined prostates were scored for accuracy. The contours were defined as ideal if they were within a 2.5-mm expansion of the standard without underestimation, acceptable if they were within a 5.0-mm expansion and a 2.5-mm de-expansion, and unacceptable if they extended >5.0 mm or underestimated the prostate by >2.5 mm. Results: A total of 636 CT slices were individually analyzed, with the vast majority scored as ideal or acceptable. However, none of the 30 prostate contour sets had all the contours scored as ideal or acceptable. For all 3 observers, the unacceptable contours were more likely from underestimation than overestimation of the prostate. The errors were more common at the base and apex than the mid-gland. Conclusions: The expansion/de-expansion tool allows for directed feedback on the location of contour deviations, as well as the determination of over- or underestimation of the prostate. This metric might help improve the accuracy of prostate contours.

  5. Speech intonation and melodic contour recognition in children with cochlear implants and with normal hearing.

    Science.gov (United States)

    See, Rachel L; Driscoll, Virginia D; Gfeller, Kate; Kliethermes, Stephanie; Oleson, Jacob

    2013-04-01

    Cochlear implant (CI) users have difficulty perceiving some intonation cues in speech and melodic contours because of poor frequency selectivity in the cochlear implant signal. To assess perceptual accuracy of normal hearing (NH) children and pediatric CI users on speech intonation (prosody), melodic contour, and pitch ranking, and to determine potential predictors of outcomes. Does perceptual accuracy for speech intonation or melodic contour differ as a function of auditory status (NH, CI), perceptual category (falling versus rising intonation/contour), pitch perception, or individual differences (e.g., age, hearing history)? NH and CI groups were tested on recognition of falling intonation/contour versus rising intonation/contour presented in both spoken and melodic (sung) conditions. Pitch ranking was also tested. Outcomes were correlated with variables of age, hearing history, HINT, and CNC scores. The CI group was significantly less accurate than the NH group in spoken (CI, M = 63.1%; NH, M = 82.1%) and melodic (CI, M = 61.6%; NH, M = 84.2%) conditions. The CI group was more accurate in recognizing rising contour in the melodic condition compared with rising intonation in the spoken condition. Pitch ranking was a significant predictor of outcome for both groups in falling intonation and rising melodic contour; age at testing and hearing history variables were not predictive of outcomes. Children with CIs were less accurate than NH children in perception of speech intonation, melodic contour, and pitch ranking. However, the larger pitch excursions of the melodic condition may assist in recognition of the rising inflection associated with the interrogative form.

  6. Hybrid OPC modeling with SEM contour technique for 10nm node process

    Science.gov (United States)

    Hitomi, Keiichiro; Halle, Scott; Miller, Marshal; Graur, Ioana; Saulnier, Nicole; Dunn, Derren; Okai, Nobuhiro; Hotta, Shoji; Yamaguchi, Atsuko; Komuro, Hitoshi; Ishimoto, Toru; Koshihara, Shunsuke; Hojo, Yutaka

    2014-03-01

    Hybrid OPC modeling is investigated using both CDs from 1D and simple 2D structures and contours extracted from complex 2D structures, which are obtained by a Critical Dimension-Scanning Electron Microscope (CD-SEM). Recent studies have addressed some of key issues needed for the implementation of contour extraction, including an edge detection algorithm consistent with conventional CD measurements, contour averaging and contour alignment. Firstly, pattern contours obtained from CD-SEM images were used to complement traditional site driven CD metrology for the calibration of OPC models for both metal and contact layers of 10 nm-node logic device, developed in Albany Nano-Tech. The accuracy of hybrid OPC model was compared with that of conventional OPC model, which was created with only CD data. Accuracy of the model, defined as total error root-mean-square (RMS), was improved by 23% with the use of hybrid OPC modeling for contact layer and 18% for metal layer, respectively. Pattern specific benefit of hybrid modeling was also examined. Resist shrink correction was applied to contours extracted from CD-SEM images in order to improve accuracy of the contours, and shrink corrected contours were used for OPC modeling. The accuracy of OPC model with shrink correction was compared with that without shrink correction, and total error RMS was decreased by 0.2nm (12%) with shrink correction technique. Variation of model accuracy among 8 modeling runs with different model calibration patterns was reduced by applying shrink correction. The shrink correction of contours can improve accuracy and stability of OPC model.

  7. Contouring a guide to the analysis and display of spatial data

    CERN Document Server

    Watson, Debbie

    2013-01-01

    This unique book is the key to computer contouring, exploring in detail the practice and principles using a personal computer. Contouring allows a three dimensional view in two dimensions and is a fundamental technique to represent spatial data. All aspects of this type of representation are covered including data preparation, selecting contour intervals, interpolation and griding, computing volumes and output and display. Formulated for both the novice and the experienced user, this book initially conducts the reader through a step by step explanation of PC software and its application to per

  8. Polar-direct-drive experiments with contoured-shell targets on OMEGA

    Science.gov (United States)

    Marshall, F. J.; Radha, P. B.; Bonino, M. J.; Delettrez, J. A.; Epstein, R.; Glebov, V. Yu.; Harding, D. R.; Stoeckl, C.; Frenje, J. A.; Gatu Johnson, M.; Séguin, F. H.; Sio, H.; Zylstra, A.; Giraldez, E.

    2016-01-01

    Polar-driven direct-drive experiments recently performed on the OMEGA Laser System have demonstrated the efficacy of using a target with a contoured shell with varying thickness to improve the symmetry and fusion performance of the implosion. The polar-driven contoured-shell implosions have substantially reduced low mode perturbations compared to polar-driven spherical-shell implosions as diagnosed by x-ray radiographs up to shell stagnation. Fusion yields were increased by more than a factor of ˜2 without increasing the energy of the laser by the use of contoured shells.

  9. Polar-direct-drive experiments with contoured-shell targets on OMEGA

    Energy Technology Data Exchange (ETDEWEB)

    Marshall, F. J.; Radha, P. B.; Bonino, M. J.; Delettrez, J. A.; Epstein, R.; Glebov, V. Yu.; Harding, D. R.; Stoeckl, C. [Laboratory for Laser Energetics, University of Rochester, 250 East River Road, Rochester, New York 14623-1299 (United States); Frenje, J. A.; Gatu Johnson, M.; Séguin, F. H.; Sio, H.; Zylstra, A. [Plasma Science and Fusion Center, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139 (United States); Giraldez, E. [General Atomics, San Diego, California 92121 (United States)

    2016-01-15

    Polar-driven direct-drive experiments recently performed on the OMEGA Laser System have demonstrated the efficacy of using a target with a contoured shell with varying thickness to improve the symmetry and fusion performance of the implosion. The polar-driven contoured-shell implosions have substantially reduced low mode perturbations compared to polar-driven spherical-shell implosions as diagnosed by x-ray radiographs up to shell stagnation. Fusion yields were increased by more than a factor of ∼2 without increasing the energy of the laser by the use of contoured shells.

  10. Subcortical neural representation to Mandarin pitch contours in American and Chinese newborns.

    Science.gov (United States)

    Jeng, Fuh-Cherng; Lin, Chia-Der; Wang, Tang-Chuan

    2016-06-01

    Voice pitch carries important information for speech understanding. This study examines the neural representation of voice pitch at the subcortical level, as reflected by the scalp-recorded frequency-following responses from ten American and ten Chinese newborns. By utilizing a set of four distinctive Mandarin pitch contours that mimic the English vowel /yi/, the results indicate that the rising and dipping pitch contours produce significantly better tracking accuracy and larger response amplitudes than the falling pitch contour. This finding suggests a hierarchy of potential stimuli when testing neonates who are born in a tonal or non-tonal linguistic environment.

  11. Autonomic Nervous System Responses to Concussion: Arterial Pulse Contour Analysis

    Directory of Open Access Journals (Sweden)

    Michael F La Fountaine

    2016-02-01

    Full Text Available The arterial pulse wave (APW has a distinct morphology whose contours reflect dynamics in cardiac function and peripheral vascular tone as a result of sympathetic nervous system (SNS control. With a transition from rest to increased metabolic demand, the expected augmentation of SNS outflow will not only affect arterial blood pressure and heart rate, it will also induce changes to the contours of the APW. Following a sports concussion, a transient state cardiovascular autonomic dysfunction is present. How this state affects the APW, has yet to be described. A prospective, parallel-group study on cardiovascular autonomic control (i.e., digital electrocardiogram and continuous beat-to-beat blood pressure was performed in the seated upright position in ten athletes with concussion and 7 non-injured control athletes. Changes in APW were compared at rest and during the first 60 seconds (F60 of an isometric handgrip test (IHGT in concussed athletes and non-injured controls within 48 hours (48hr and 1 week (1wk of injury. The concussion group was further separated by the length of time until they were permitted to return to play (RTP>1wk; RTP≤1wk. SysSlope, an indirect measurement of stroke volume, was significantly lower in the concussion group at rest and during F60 at 48hr and 1wk; a paradoxical decline in SysSlope occurred at each visit during the transition from rest to IHGT F60. The RTP>1wk group had lower SysSlope (405±200; 420±88; 454±236 mmHg/s, respectively at rest 48hr compared to the RTP≤1wk and controls. Similarly at 48hr rest, several measurements of arterial stiffness were abnormal in RTP>1wk compared to RTP≤1wk and controls: Peak-to-Notch Latency (0.12±0.04; 0.16±0.02; 0.17±0.05, respectively, Notch Relative Amplitude (0.70±0.03; 0.71±0.04; 0.66±0.14, respectively and Stiffness Index (6.4±0.2; 5.7±0.4; 5.8±0.5, respectively. Use of APW revealed that concussed athletes have a transient increase in peripheral artery

  12. 网络信息加密RSA算法的运算速度和保密性优化%Optimization of Operation Speed and Confidentiality of Network Information Encryption RSA Algorithm

    Institute of Scientific and Technical Information of China (English)

    许柯; 刘绪崇; 符振艾; 徐宇宏

    2015-01-01

    According to traditional RSA algorithm has low speed of computing and bad encryption result for encrypting the network information, this article puts forward the RSA encryption algorithm of network information with relevant improved SMM algorithm. The first step is to optimize the modulus and multiplication time of SMM algorithm, the second step is to use the improved SMM algorithm to optimize the RSA algorithm, aiming at the modified algorithm of binary hamming weight in the index, the purpose is to reduce the iteration number, eventually improve the encryption of original algorithm. Seen from the algorithm simulation results, compared with SMM algorithm, the proposed RSA network information encryption algorithm based on improved SMM algorithm and traditional RSA encryption algorithm has faster process of encryption and decryption, and has stronger encryption effect.%针对传统RSA算法在对网络信息进行加密的时候还存在运算速度不快、加密效果不好的问题,本文提出有关改进SMM算法的RSA网络信息加密算法,第一步是针对SMM算法的求模运算量以及乘法时间进行优化操作,第二步是使用改进的SMM算法对RSA算法进行优化,针对其算法的二进制指数中的汉明重量进行改良,目的是为了减少迭代数,最终提升原来算法的加密功能。通过算法仿真实验结果可以看出,本文提出的基于改进SMM算法的RSA网络信息加密算法以及传统RSA加密算法,再与SMM算法进行比较,加密以及解密过程的速度更快,并且加密效果更强。

  13. Perceived Blur in Naturally-Contoured Images Depends on Phase

    Directory of Open Access Journals (Sweden)

    Stephanie Murray

    2010-12-01

    Full Text Available Perceived blur is an important measure of image quality and clinical visual function. The magnitude of image blur varies across space and time under natural viewing conditions owing to changes in pupil size and accommodation. Blur is frequently studied in the laboratory with a variety of digital filters, without comparing how the choice of filter affects blur perception. We examine the perception of image blur in synthetic images composed of contours whose orientation and curvature spatial properties matched those of natural images but whose blur could be directly controlled. The images were blurred by manipulating the slope of the amplitude spectrum, Gaussian low-pass filtering or filtering with a Sinc function, which, unlike slope or Gaussian filtering, introduces periodic phase reversals similar to those in optically blurred images. For slope-filtered images, blur discrimination thresholds for over-sharpened images were extremely high and perceived blur could not be matched with either Gaussian or Sinc filtered images, suggesting that directly manipulating image slope does not simulate the perception of blur. For Gaussian and Sinc blurred images, blur discrimination thresholds were dipper-shaped and were well-fit with a simple variance discrimination model and with a contrast detection threshold model, but the latter required different contrast sensitivity functions for different types of blur. Blur matches between Gaussian and Sinc blurred images were used to test several models of blur perception and were in good agreement with models based on luminance slope, but not with spatial frequency based models. Collectively, these results show that the relative phases of image components, in addition to their relative amplitudes, determines perceived blur.

  14. New method of contour-based mask-shape compiler

    Science.gov (United States)

    Matsuoka, Ryoichi; Sugiyama, Akiyuki; Onizawa, Akira; Sato, Hidetoshi; Toyoda, Yasutaka

    2007-10-01

    We have developed a new method of accurately profiling a mask shape by utilizing a Mask CD-SEM. The method is intended to realize high accuracy, stability and reproducibility of the Mask CD-SEM adopting an edge detection algorithm as the key technology used in CD-SEM for high accuracy CD measurement. In comparison with a conventional image processing method for contour profiling, it is possible to create the profiles with much higher accuracy which is comparable with CD-SEM for semiconductor device CD measurement. In this report, we will introduce the algorithm in general, the experimental results and the application in practice. As shrinkage of design rule for semiconductor device has further advanced, an aggressive OPC (Optical Proximity Correction) is indispensable in RET (Resolution Enhancement Technology). From the view point of DFM (Design for Manufacturability), a dramatic increase of data processing cost for advanced MDP (Mask Data Preparation) for instance and surge of mask making cost have become a big concern to the device manufacturers. In a sense, it is a trade-off between the high accuracy RET and the mask production cost, while it gives a significant impact on the semiconductor market centered around the mask business. To cope with the problem, we propose the best method for a DFM solution in which two dimensional data are extracted for an error free practical simulation by precise reproduction of a real mask shape in addition to the mask data simulation. The flow centering around the design data is fully automated and provides an environment where optimization and verification for fully automated model calibration with much less error is available. It also allows complete consolidation of input and output functions with an EDA system by constructing a design data oriented system structure. This method therefore is regarded as a strategic DFM approach in the semiconductor metrology.

  15. Computer-aided measurement of liver volumes in CT by means of geodesic active contour segmentation coupled with level-set algorithms

    Energy Technology Data Exchange (ETDEWEB)

    Suzuki, Kenji; Kohlbrenner, Ryan; Epstein, Mark L.; Obajuluwa, Ademola M.; Xu Jianwu; Hori, Masatoshi [Department of Radiology, University of Chicago, 5841 South Maryland Avenue, Chicago, Illinois 60637 (United States)

    2010-05-15

    Purpose: Computerized liver extraction from hepatic CT images is challenging because the liver often abuts other organs of a similar density. The purpose of this study was to develop a computer-aided measurement of liver volumes in hepatic CT. Methods: The authors developed a computerized liver extraction scheme based on geodesic active contour segmentation coupled with level-set contour evolution. First, an anisotropic diffusion filter was applied to portal-venous-phase CT images for noise reduction while preserving the liver structure, followed by a scale-specific gradient magnitude filter to enhance the liver boundaries. Then, a nonlinear grayscale converter enhanced the contrast of the liver parenchyma. By using the liver-parenchyma-enhanced image as a speed function, a fast-marching level-set algorithm generated an initial contour that roughly estimated the liver shape. A geodesic active contour segmentation algorithm coupled with level-set contour evolution refined the initial contour to define the liver boundaries more precisely. The liver volume was then calculated using these refined boundaries. Hepatic CT scans of 15 prospective liver donors were obtained under a liver transplant protocol with a multidetector CT system. The liver volumes extracted by the computerized scheme were compared to those traced manually by a radiologist, used as ''gold standard.''Results: The mean liver volume obtained with our scheme was 1504 cc, whereas the mean gold standard manual volume was 1457 cc, resulting in a mean absolute difference of 105 cc (7.2%). The computer-estimated liver volumetrics agreed excellently with the gold-standard manual volumetrics (intraclass correlation coefficient was 0.95) with no statistically significant difference (F=0.77; p(F{<=}f)=0.32). The average accuracy, sensitivity, specificity, and percent volume error were 98.4%, 91.1%, 99.1%, and 7.2%, respectively. Computerized CT liver volumetry would require substantially less

  16. RSA算法中Z*(φ)(n)的代数结构研究%Study on Algebraic Structure of Z*(φ)(n) in RSA Algorithm

    Institute of Scientific and Technical Information of China (English)

    裴东林; 胡建军; 李旭

    2013-01-01

    [Abstract] Based on the theory of quadratic residues, this paper considers the algebraic structure of Z*φ(n) in the two order strong RSA algorithm. It is proved that the element α of Z*φ(n) gets maximal order if and only if gcd(α±l,n1) = 1, and the numbers of quadratic residues in the group Z*φ(n) is φ(φ(n))/8 .Z*φ(n) is divided up by the group which is composed of all quadratic residues, and all cosets form a Klein eight-group. It proves that the group Z*φ(n) can be generated by seven elements of quadratic non-residues.%应用二次剩余理论,对二阶强RSA算法中Z*(φ)(n)的代数结构进行研究,证明Z*(φ)(n)中元素a取最大阶的充要条件为gcd(a±1,n1)=1,以及任意元素的阶Z*(φ)(n)中模(φ)(n)的二次剩余个数为(φ)(φ)(n))/8,以所有二次剩余构成的群对Z*(φ)(n)进行分割,利用所有陪集构成一个Klein八元群,在此基础上证明Z*(φ)(n)可由7个二次非剩余元素生成.

  17. Displacement of the medial meniscus within the passive motion characteristics of the human knee joint: an RSA study in human cadaver knees.

    Science.gov (United States)

    Tienen, T G; Buma, P; Scholten, J G F; van Kampen, A; Veth, R P H; Verdonschot, N

    2005-05-01

    The objective of this study was to validate an in vitro human cadaver knee-joint model for the evaluation of the meniscal movement during knee-joint flexion. The question was whether our model showed comparable meniscal displacements to those found in earlier meniscal movement studies in vivo. Furthermore, we determined the influence of tibial torque on the meniscal displacement during knee-joint flexion. Three tantalum beads were inserted in the medial meniscus of six human-cadaver joints. The knee joints were placed and loaded in a loading apparatus, and the movements of the beads were determined by means of RSA during knee-joint flexion and extension with and without internal tibial (IT) and external tibial (ET) torque. During flexion without tibial torque, all menisci moved in posterior and lateral direction. The anterior horn showed significantly greater excursions than the posterior horn in both posterior and lateral direction. Internal tibial torque caused an anterior displacement of the pathway on the tibial plateau. External tibial torque caused a posterior displacement of the pathway. External tibial torque restricted the meniscal displacement during the first 30 degrees of knee-joint flexion. The displacements of the meniscus in this experiment were similar to the displacements described in the in vivo MRI studies. Furthermore, the application of tibial torque confirmed the relative immobility of the posterior horn of the meniscus. During external tibial torque, the posterior displacement of the pathway on the tibial plateau during the first 30 degrees of flexion might be restricted by the attached knee-joint capsule or the femoral condyle. This model revealed representative meniscal displacements during simple knee-joint flexion and also during the outer limits of passive knee-joint motion.

  18. Structural contours of the Hauterivian Qezeltash formation of northern Afghanistan (qezeldpafg.shp)

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This shapefile contains polylines that describe structural contours (subsea elevation) of the Hauterivian Qezeltash formation in northern Afghanistan. Hauterivian...

  19. bathy_500m - 500m Bathy Contours Derived from ETOPO2 Global 2' Elevations

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This bathymetry contour data is in ESRI shapefile format and was derived from a National Oceanic Atmospheric Administration (NOAA), National Geophysical Data Center...

  20. Scale and Contour: Two Components of a Theory of Memory for Melodies.

    Science.gov (United States)

    Dowling, W. Jay

    1978-01-01

    The author concentrates on two components of memory which contribute to the reproduction and recognition of melodies, namely, melodic contour and musical scale. A new experiment is reported that shows the interdependence of both components. (Author/RK)

  1. National Assessment of Oil and Gas Project - Uinta-Piceance Province (020) Maturation Contours

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — The maturation contours show vitrinite reflectance trends and ranges for five key petroleum system horizons within the Uinta-Piceance Province. The horizons are the...

  2. Structural contours of the Upper Campanian through Paleocene Ghory formation of northern Afghanistan (ghorydpafg.shp)

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This shapefile contains polylines that describe structural contours of subsea elevation of the top of the Upper Campanian through Paleocene Ghory formation in...

  3. VT 1 ft Contour Lines generated from bare earth lidar - 60% of VT

    Data.gov (United States)

    Vermont Center for Geographic Information — (Link to Metadata) This metadata applies to contours derived from Quality Level 2 (QL2) Lidar "collections" with a resolution (RESCLASS) of 0.7m. For an overview of...

  4. Mahogany Ledge Digital Structure Contour Lines of the Piceance Basin, Colorado

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — The Mahogany ledge structure contour lines were needed to perform overburden calculations in the Piceance Basin, Colorado as part of a 2009 National Oil Shale...

  5. Structure Contour of the Top of the Lower Miocene 2 Sequence, Gulf Coast

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — The structure contours were created using biostratigraphic data in the Paleo-Data, Inc., Tenroc Regional Geologic Database. The depths of the microfossil locations...

  6. Age-related changes in visual contour integration: implications for physiology from psychophysics.

    Science.gov (United States)

    Hipp, D; Dickerson, K; Moser, A; Gerhardstein, Peter

    2014-09-01

    Visual contour detection is enhanced by grouping principles, such as proximity and collinearity, which appear to rely on horizontal connectivity in visual cortex. Previous experiments suggest that children require greater proximity to detect contours and that, unlike adults, collinearity does not compensate for their proximity limitation. Over two experiments we test whether closure, a global property known to facilitate contour detection, compensates for this limitation. Adults and children (3-9 years old) performed a 2AFC task; one panel contained an illusory contour (closed or open) in visual noise, and one only noise. The experiments were identical except proximity was doubled in Exp. 2, enabling shorter-range spatial integration. Results suggest children are limited by proximity, and that closure did not reliably improve their performance as it did for adults. We conclude that perceptual maturity lags behind anatomy within this system, and suggest that slow statistical learning of long-range orientation correlations controls this disparity. © 2014 Wiley Periodicals, Inc.

  7. USGS Small-scale Dataset - 1:1,000,000-Scale Contours of Alaska 201404 Shapefile

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This map layer shows elevation contour lines for Alaska. The map layer was derived from the 100-meter resolution elevation data set which is published by the...

  8. Sensitivity adjustable contouring by digital holography and a virtual reference wavefront

    Science.gov (United States)

    Cai, L. Z.; Liu, Q.; Yang, X. L.; Wang, Y. R.

    2003-06-01

    A new method of contouring using digital holography and a virtual reference wavefront is reported. In this method, an object wave is first recorded and then digitally reconstructed. At the same time, a reference wave is digitally introduced to interfere with the reconstructed object wave to form a contour pattern. Since the form or curvature of the reference wave can be arbitrarily designed and artificially generated by a computer, the contouring sensitivity (the depth interval) can be easily adjusted for different purpose. The effectiveness of this method has been verified by computer simulations with both the conventional off-axis hologram and the phase-shifting hologram. The simplicity of optical setup and the unique ability of changing contouring sensitivity in this technique make it attractive potential in practical measurements.

  9. Active Contour Model Coupling with Higher Order Diffusion for Medical Image Segmentation

    Directory of Open Access Journals (Sweden)

    Guodong Wang

    2014-01-01

    Full Text Available Active contour models are very popular in image segmentation. Different features such as mean gray and variance are selected for different purpose. But for image with intensity inhomogeneities, there are no features for segmentation using the active contour model. The images with intensity inhomogeneities often occurred in real world especially in medical images. To deal with the difficulties raised in image segmentation with intensity inhomogeneities, a new active contour model with higher-order diffusion method is proposed. With the addition of gradient and Laplace information, the active contour model can converge to the edge of the image even with the intensity inhomogeneities. Because of the introduction of Laplace information, the difference scheme becomes more difficult. To enhance the efficiency of the segmentation, the fast Split Bregman algorithm is designed for the segmentation implementation. The performance of our method is demonstrated through numerical experiments of some medical image segmentations with intensity inhomogeneities.

  10. VT 100 ft Contour Lines generated from USGS 30 meter NED DEM

    Data.gov (United States)

    Vermont Center for Geographic Information — (Link to Metadata) This data layers consists of 100 foot contours intervals interpolated from the USGS NED. USGS NED (National Elevation Dataset) data are described...

  11. 1:1,000,000-Scale Contours of the Conterminous United States - Direct Download

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This map layer shows elevation contour lines for the conterminous United States. The map layer was derived from the 100-meter resolution elevation data set which is...

  12. USGS Small-scale Dataset - 1:1,000,000-Scale Contours of Hawaii 201404 Shapefile

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This map layer shows elevation contour lines for Hawaii. The map layer was derived from the 100-meter resolution elevation data set which is published by the...

  13. A multi-scale approach to mass segmentation using active contour models

    Science.gov (United States)

    Yu, Hongwei; Li, Lihua; Xu, Weidong; Liu, Wei

    2010-03-01

    As an important step of mass classification, mass segmentation plays an important role in computer-aided diagnosis (CAD). In this paper, we propose a novel scheme for breast mass segmentation in mammograms, which is based on level set method and multi-scale analysis. Mammogram is firstly decomposed by Gaussian pyramid into a sequence of images from fine to coarse, the C-V model is then applied at the coarse scale, and the obtained rough contour is used as the initial contour for segmentation at the fine scale. A local active contour (LAC) model based on image local information is utilized to refine the rough contour locally at the fine scale. In addition, the feature of area and gray level extracted from coarse segmentation is used to set the parameters of LAC model automatically to improve the adaptivity of our method. The results show the higher accuracy and robustness of the proposed multi-scale segmentation method than the conventional ones.

  14. A multiresolution framework for ultrasound image segmentation by combinative active contours.

    Science.gov (United States)

    Wang, Weiming; Qin, Jing; Chui, Yim-Pan; Heng, Pheng-Ann

    2013-01-01

    We propose a novel multiresolution framework for ultrasound image segmentation in this paper. The framework exploits both local intensity and local phase information to tackle the degradations of ultrasound images. First, multiresolution scheme is adopted to build a Gaussian pyramid for each speckled image. Speckle noise is gradually smoothed out at higher levels of the pyramid. Then local intensity-driven active contours are employed to locate the coarse contour of the target from the coarsest image, followed by local phase-based geodesic active contours to further refine the contour in finer images. Compared with traditional gradient-based methods, phase-based methods are more suitable for ultrasound images because they are invariant to variations in image contrast. Experimental results on left ventricle segmentation from echocardiographic images demonstrate the advantages of the proposed model.

  15. Potentiometric water-level altitude contours of Dixie Valley, west-central Nevada

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This data set contains the potentiometric water-level altitude contours representing the 2009 potentiometric surface of the basin fill groundwater system of Dixie...

  16. Depth Contours for select locations across the U.S. Pacific Islands

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — These data are depth contours (isobaths) derived at 50 meters for most islands and reefs in the Mariana Archipelago, American Samoa, and the Pacific Remote Island...

  17. VT 50 foot contours generated from USGS 30 meter NED DEM

    Data.gov (United States)

    Vermont Center for Geographic Information — (Link to Metadata) This data layers consists of 50 foot contours intervals interpolated from the USGS NED. USGS NED (National Elevation Dataset) data are described...

  18. A new approach of drawing airport noise contours on computer based on Surfer

    Institute of Scientific and Technical Information of China (English)

    ZHANG Bang-jun; GUO Chun-yan; Di Guo-qing

    2004-01-01

    Noise contours are used to describe the extent of airport noise pollution and to plan land use around airports. The LwEcPN (weighted equivalent continuous perceive noise level) recommended by ICAO(International Civil Aviation Organization ) is adopted as airport noise rating parameter in this paper. With the help of various mathematical models in the software Surfer, noise contours can be drawn automatically by the completed program in Visual C++ Code. Corrections for thrust, velocity, atmospheric temperature, humidity and lateral ground attenuation are also considered in the new method, which can improve the efficiency of drawing contours. An example of its use for drawing noise contours of an airport in Zhejiang Province of China is proposed and the predictions and the measurements show agreements well.

  19. 1:1,000,000-Scale Contours of Alaska - Direct Download

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This map layer shows elevation contour lines for Alaska. The map layer was derived from the 100-meter resolution elevation data set which is published by the...

  20. Contours, Published in 1995, 1:4800 (1in=400ft) scale, Greenwood County.

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — This Contours dataset, published at 1:4800 (1in=400ft) scale, was produced all or in part from Orthoimagery information as of 1995. Data by this publisher are often...