• ETRI Journal
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• v.43 no.1
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• pp.109-119
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• 2021

Self-recovery is a tamper-detection and image recovery methods based on data hiding. It generates two types of data and embeds them into the original image: authentication data for tamper detection and reference data for image recovery. In this paper, a region-based scalable self-recovery (RSS) method is proposed for salient-object images. As the images consist of two main regions, the region of interest (ROI) and the region of non-interest (RONI), the proposed method is aimed at achieving higher reconstruction quality for the ROI. Moreover, tamper tolerability is improved by using scalable recovery. In the RSS method, separate reference data are generated for the ROI and RONI. Initially, two compressed bitstreams at different rates are generated using the embedded zero-block coding source encoder. Subsequently, each bitstream is divided into several parts, which are protected through various redundancy rates, using the Reed-Solomon channel encoder. The proposed method is tested on 10 000 salient-object images from the MSRA database. The results show that the RSS method, compared to related methods, improves reconstruction quality and tamper tolerability by approximately 30% and 15%, respectively.

• Journal of the Korean Statistical Society
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• v.19 no.1
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• pp.88-92
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• 1990

In the problem of the recovery of interblock information in balanced incomplete block designs(BIBD), it is well known that a truncated estimator dominates the untruncated estimator under mean squared error loss. This paper shows that the domination result holds universally for every nondecreasing loss function.

• The Korean Journal of Pain
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• v.27 no.3
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• pp.210-218
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• 2014

Brachial plexus injury is a potential complication of a brachial plexus block or vessel puncture. It results from direct needle trauma, neurotoxicity of injection agents and hematoma formation. The neurological presentation may range from minor transient pain to severe sensory disturbance or motor loss with poor recovery. The management includes conservative treatment and surgical exploration. Especially if a hematoma forms, it should be removed promptly. Comprehensive knowledge of anatomy and adept skills are crucial to avoid nerve injuries. Whenever possible, the patient should not be heavily sedated and should be encouraged to immediately inform the doctor of any experience of numbness/paresthesia during the nerve block or vessel puncture.

• Journal of Yeungnam Medical Science
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• v.35 no.1
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• pp.104-108
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• 2018

Syncope is defined as a transient loss of consciousness and postural tone, characterized by rapid onset, short duration, and spontaneous recovery. Stellate ganglion block (SGB) is a nerve block method that is used for treatment of neuropathic pain in the head, neck and upper extremities, especially trigeminal neuralgia, postherpetic neuralgia and complex regional pain syndrome. SGB can modulate and stabilize the sympathetic nervous system, which prevents it from overexcitation and improves symptoms of syncope. The authors report a patient who was treated for pain and edema of both upper extremities with SGB, then showed improvement in recurrent syncope followed by chest pain and overall quality of life.

• Journal of the Korea Society of Computer and Information
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• v.23 no.1
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• pp.57-66
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• 2018

It is known that a single-key and a related-key attacks on AES-128 are possible for at most 7 and 8 rounds, respectively. The security of CMAC, a typical block-cipher-based MAC algorithm, has very high possibility of inheriting the security of the underlying block cipher. Since the attacks on the underlying block cipher can be applied directly to the first block of CMAC, the current security margin is not sufficient compared to what the designers of AES claimed. In this paper, we consider HMAC-DM-AES-128 as an alternative to CMAC-AES-128 and analyze its security for reduced rounds of AES-128. For 2-round AES-128, HMAC-DM-AES-128 requires the precomputation phase time complexity of $2^{97}$ AES, the online phase time complexity of $2^{98.68}$ AES and the data complexity of $2^{98}$ blocks. Our work is meaningful in the point that it is the first security analysis of MAC based on hash modes of AES.

• The Korean Journal of Pain
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• v.9 no.1
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• pp.260-263
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• 1996

High spinal block is a rare complication during epidural block, but it may result in serious events. 56-year-old man with gall stones was scheduled for cholecystectomy under general anesthesia. After operation, lumbar epidural catheterization was done at $T_{8-9}$ interspace for postoperative pain control. At the recovery room, initial bolus drug (0.1% bupivacaine 10 ml containing fentanyl $100{\mu}g$) was administered via epidural catheter and observed carefully. 15 minutes later, hypotension and bradycardia ouccurred. Hartman' solution was administered rapidly and ephedrine 5 mg was injected. 30 minutes after drug administration, loss of consciousness and respiratory arrest developed. Tracheal intubation was done immediately. Cardiovascular and respiratory functions were monitored continuously. The location of intrathecal catheter was confirmed by cerebrospinal fluid (CSF) seen in syringe after aspiration of catheter. The patient recovered gradually and was placed in the ward 4 hours after drug administration, without any problems. He was discharged 1 week later in good health.

• The Korean Journal of Pain
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• v.19 no.2
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• pp.164-167
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• 2006

Background: There have been an increasing number of reports about infection-related complications after epidural block, and the analysis of these previous reports may offer valuable information for the prevention and treatment of such complications. Methods: We searched for complications about infection that was related to epidural blockade procedures by using the Medline Search program. We analyzed the types of infection-related complications as well as the potential risk factors, the time course from symptom development to treatment, the causative organisms and the treatment outcomes. Results: Seventeen cases were identified. The types of complications were epidural abscess, subdural abscess, spinal arachnoiditis, bacterial meningitis and aseptic meningitis. Five patients received a single block and twelve patients received a continuous block with catheterization. The most common site of epidural catheterization was the lumbar area and eight patients had indwelling catheters for less than fifteen days. Eight patients had a diabetes mellitus as a risk factor and fourteen patients showed less than seven days from the development of symptoms to treatment. Eleven patients received laminectomy and intravenous antibiotics as a treatment and eight patients had full recovery without neurological deficit. Conclusions: Early diagnosis and treatment is essential for the favorable outcome of infection-related complication after epidural block. In addition, absolute sterile technique should always be performed and patient education concerning these potential complications must be accompanied.

• Journal of Microbiology and Biotechnology
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• v.19 no.10
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• pp.1230-1237
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• 2009

The selective plugging strategy of Microbial Enhanced Oil Recovery (MEOR) involves the use of microbes that grow and produce exopolymeric substances, which block the high permeability zones of an oil reservoir, thus allowing the water to flow through the low permeability zones leading to increase in oil recovery. Bacillus licheniformis TT33, a hot water spring isolate, is facultatively anaerobic, halotolerant, and thermotolerant. It produces EPS as well as biosurfactant and has a biofilm-forming ability. The viscosity of its cell-free supernatant is $120\;mPa{\cdot}s$ at $28^{\circ}C$. Its purified EPS contained 26% carbohydrate and 3% protein. Its biosurfactant reduced the surface tension of water from 72 to 34 mN/m. This strain gave $27.7{\pm}3.5%$ oil recovery in a sand pack column. Environmental scanning electron microscopy analysis showed bacterial growth and biofilm formation in the sand pack. Biochemical tests and Amplified Ribosomal DNA Restriction Analysis confirmed that the oil recovery obtained in the sand pack column was due to Bacillus licheniformis TT33.

• Journal of the Institute of Electronics Engineers of Korea SP
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• v.42 no.5 s.305
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• pp.95-102
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• 2005

When images compressed with block-based compression techniques are transmitted over a noisy channel, unexpected block losses occur. In this paper, we present a post-processing-based block recovery scheme using Haar wavelet features. No consideration of the edge-direction, when recover the lost blocks, can cause block-blurring effects. The proposed directional recovery method in this paper is effective for the strong edge because exploit the varying neighboring blocks adaptively according to the edges and the directional information in the image. First, the adaptive selection of neighbor blocks is performed based on the energy of wavelet subbands (EWS) and difference of DC values (DDC). The lost blocks are recovered by the linear interpolation in the spatial domain using selected blocks. The method using only EWS performs well for horizontal and vertical edges, but not as well for diagonal edges. Conversely, only using DDC performs well diagonal edges with the exception of line- or roof-type edge profiles. Therefore, we combined EWS and DDC for better results. The proposed methods out performed the previous methods using fixed blocks.

• Journal of Broadcast Engineering
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• v.4 no.1
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• pp.76-85
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• 1999

The degradation of image quality by block loss is more serious in fractal coded images with the error propagation due to mapping from the lost blocks than in DCT coded images. Therefore. a new algorithm is presented for recovering the blocks lost in the transmission through the lossy network as A TM network of the images coded by Jacquins fractal coding. Jacquins fractal code is divided into two layers of header code and main code according to its importance. The key technique of the proposed BLRA (block loss recovery algorithm) is a fractal extrapolation that estimates the lost pixels by using the contractive mapping parameters of the neighboring range blocks whose characteristics are similar to a lost block. The proposed BLRA is applied to the lost blocks in the iteration of decoding. Some experimental results show the proposed BLRA yields excellent performance in PSNR as well as subjective quality.