• Journal of Digital Contents Society
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• v.5 no.2
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• pp.101-105
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• 2004

The block error probabilities of noncoherent frequency shift keying in a Nakagami fading channel are presented in this papaer. The channel fading speed, show or fast. is consider in evaluating block error probabilities. The effectiveness of diversity combing and error correction coding in improving block error performance is examined. The effect of cochannel interference on block error performance is also studied in this paper.

• Journal of applied mathematics & informatics
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• v.16 no.1_2
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• pp.207-220
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• 2004

Necessary and sufficient conditions are given for the regularity of block triangular fuzzy matrices. This leads to characterization of idem-potency of a class of triangular Toeplitz matrices. As an application, the existence of group inverse of a block triangular fuzzy matrix is discussed. Equivalent conditions for a regular block triangular fuzzy matrix to be expressed as a sum of regular block fuzzy matrices is derived. Further, fuzzy relational equations consistency is studied.

• Journal of Chest Surgery
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• v.26 no.10
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• pp.781-786
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• 1993

Effrctive analgesia after elective thoracotomy can be provided by continuous extrapleural intercostal nerve block.This study was designed to prove the effectiveness of continuous extrapleural intercostal nerve block. Twenty patients undergoing elective thoracotomy were randomized into two groups. Group I received lumbar epidural block[N=10] and group II received continuous extrapleural intercostal nerve block[N=10]. Postoperative pain relief was assessed on Numeric Rating Scale[NRS] and recovery of pulmonary function was assessed by coparison of preoperatrive and postoperative FVC[Forced Vital Capacity], FEV1[Forced expiratory Volume in 1 second], VC[Vital Capacity]. Arterial blood gas analysis[ABGA], vital signs and amount of additive analgesics were compared also. No significant difference was observed between the groups concerning these parameters mentioned above. Systemic complications, such as urinary retention[2/10] and weakness of lower extremity[2/10], occurred in group I but no complication occurred in group II. We conclude that continuous extrapleural intercostal nerve block is as effective as epidural block in pain relief and restoration of pulmonary mechanics with fewer comlications. Also because of it`s ease and safetiness, this must be considered as a substitute of epidural block in routine use for thoracotomy pain relief.

• The Korean Journal of Pain
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• v.8 no.2
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• pp.304-307
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• 1995

1,666 patients treated by nerve block from September 1994 to August 1995 we statistically analyzed according to sex, age, diseases, and kinds of nerve blocks. Most patients were in the range from 30 to 60 year old, with a distribution of 43.9% male and 56.1% female. Diseases and ailments were as follows: low back pain 30.6%, frozen shoulder 14.0%, facial spasm 10.0%, cervical syndrome 9.7%, headache 7.3%, and hyperhidrosis 7.2%. Most common nerve blocks were stellate ganglion block 30.9%, epidural block 25.6%, trigger point injection 16.1%, and suprascapular nerve block 6.7%. Nerve blocks under fluoroscopic guide were as follows: facet joint block 28.6%, spinal root block 22.9%, thoracic sympathetic ganglion block 21.7%, and lumbar sympathetic ganglion block 15.4%.

• KIPS Transactions on Computer and Communication Systems
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• v.4 no.3
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• pp.105-108
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• 2015

In this paper, we propose a differential fault analysis on symmetric SPN block cipher with bitslice involution S-box in 2011. The target block cipher was designed using AES block cipher and has advantage about restricted hardware and software environment using the same structure in encryption and decryption. Therefore, the target block cipher must be secure for the side-channel attacks. However, to recover the 128-bit secret key of the targer block cipher, this attack requires only one random byte fault and an exhausted search of $2^8$. This is the first known cryptanalytic result on the target block cipher.

• Polymer(Korea)
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• v.27 no.1
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• pp.17-25
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• 2003

Using atom transfer radical polymerization (ATRP), polystyrene macroinitiators and polystyrene-b-poly(t-butyl acrylate) (PS-b-P(tBA) block copolymers were synthesized by CuBr/PMDETA catalyst system in solution. After hydrolysis, polystyrene-b-poly(acrylic acid), amphiphilic block copolymers, were formed. Subsequent neutralization of polyacid block led to the block ionomers. The molecular weight of the synthesized PS-b-P(tBA) block copolymers was easily-controlled to 5000-10000 and their distributions were less than 1.2. The chemical structures of the synthesized block copolymers were characterized by $^1$H-NMR and FT-IR. In the DSC thermograms, $T_g$ appeared in the vicinity of 100 $^{\circ}C$ because of higher styrene content. In addition, the phase separation of the block ionomers was observed by TEM.

• The Korean Journal of Pain
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• v.24 no.1
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• pp.31-35
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• 2011

Background: Circumcision is a painful intervention frequently performed in pediatric surgery. We aim to compare the efficacy of caudal block versus dorsal penile block (DPNB) under general anesthesia for children undergoing circumcision. Methods: This study was performed between July 1, 2009 and October 16, 2009. Fifty male children American Society of Anesthesiolgists physical status classification I, aged between 3 and 12 were included in this randomized, prospective, comparative study. Anesthetic techniques were standardized for all children. Patients were randomized into 2 groups. Using 0.25% 0.5 ml/kg levobupivacain, we performed DPNB for Group 1 and caudal block for Group 2. Postoperative analgesia was evaluated for six hours with the Flacc Pain Scale for five categories; (F) Face, (L) Legs, (A) Activity, (C) Cry, and (C) Consolability. For every child, supplemental analgesic amounts, times, and probable local or systemic complications were recorded. Results: No significant difference between the groups (P > 0.05) was found in mean age, body weight, anesthesia duration, FLACC pain, and sedation scores (P > 0.05). However, on subsequent measurements, a significant decrease of pain and sedation scores was noted in both the DPNB group and the caudal block group (P < 0.001). No major complication was found when using either technique. Conclusions: DPNB and caudal block provided similar postoperative analgesic effects without major complications for children under general anesthesia.

• Journal of the Society of Naval Architects of Korea
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• v.58 no.2
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• pp.84-89
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• 2021

Recently, shipyards are making many efforts to reduce the number of the mounted blocks by increasing the block size. This is to improve productivity and reduce related costs by minimizing block movement and shortening the building period. However, as the blocks become larger, the weight increases considerably. If the target block has a damage due to an unexpected accident during block lifting, it may seriously cause a problem of the reusability of the block. In this study, a large-sized block of the offshore structure weighing 480 tons was lifting with a total of seven sling belts, and one sling belt was broken while it was moving, resulting in a situation in which a part of the edge of the block collided with the ground. The aim of this paper is to verify the structural integrity of the block that directly collides with the ground in the form of free fall due to the sling breakage. Considering that the hook loads acting on several sling belts holding the block are redistributed when a sling belt is broken, the hook loads were recalculated at the angle just before the sling breakage. These loads were used to check the safety of the sling belts. In addition, FE analysis was performed by calculating the amount of impact from the free fall condition, obtaining the impact area by using Hertz's contact theory, and then applying the impact load to the area.

• Korea-Australia Rheology Journal
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• v.13 no.2
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• pp.83-87
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• 2001

The morphology and mechanical properties of the blends of a syndiotactic polystyrene (SPS) and poly-styrene-block-poly(ethylene-co-butylene)-block-polystyrene copolymers (SEBS) with various polystyrene block contents are studied. Mechanical properties, especially elongation at break and impact strength (IS), of the blend depend upon the morphology and interfacial adhesion, which in rum are affected by the viscosity ratio of constituent components and the styrene block content in SEBS. The IS of a blend was affected by the combined effect of rubber content and the interfacial adhesion. A maximum IS was found for a blend with the weight fraction of the PS block in an SEBS of 0.18. The IS of blends with smaller weight fractions of the PS block exhibited lower due to poor interfacial adhesion between SPS/SEBS in spite of a larger amount of rubber block. On the other hand, the IS of blends with larger weight fraction of the PS block becomes smaller due to lower amounts of rubber block in spite of better interfacial adhesion.

• Journal of electromagnetic engineering and science
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• v.6 no.4
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• pp.244-252
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• 2006

A block Jacket transform and. its block inverse Jacket transformn have recently been reported in the paper 'Fast block inverse Jacket transform'. But the multiplication of the block Jacket transform and the corresponding block inverse Jacket transform is not equal to the identity transform, which does not conform to the mathematical rule. In this paper, new binary block Jacket transforms and the corresponding binary block inverse Jacket transforms of orders $N=2^k,\;3^k\;and\;5^k$ for integer values k are proposed and the mathematical proofs are also presented. With the aid of the Kronecker product of the lower order Jacket matrix and the identity matrix, the fast algorithms for realizing these transforms are obtained. Due to the simple inverse, fast algorithm and prime based $P^k$ order of proposed binary block inverse Jacket transform, it can be applied in communications such as space time block code design, signal processing, LDPC coding and information theory. Application of circular permutation matrix(CPM) binary low density quasi block Jacket matrix is also introduced in this paper which is useful in coding theory.