• Journal of Chest Surgery
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• v.16 no.4
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• pp.506-510
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• 1983

Valve dysfunction can be caused by thickening or contraction of a fibrous sheath covering a cusp of a porcine bioprosthesis, but this is uncommon. This complication appears to more frequent in other bioprostheses, such as fascia late valves and homografts, in which fibrous sheaths seems to grow more rapidly. rapidly. Thus the slow and limited growth of fibrous sheath in porcine bioprostheses is advantageous in this respect. Recently, we experienced a case of valve dysfunction caused by fibrous tissue overgrowth on Hancock mitral xenograft in 45 year old female. 3.5 years ago, the patient was received valve replacement due to mitral stenoinsufficiency. But since 2.5 years elapsed after operation, she has complained of generalized edema and dyspnea, and their symptoms were aggravated progressively. So reoperation was performed under the diagnosis as valve dysfunction of mitral xenograft and newly developed tricuspid insufficiency. Her postoperative courses were good.

• Proceedings of the IEEK Conference
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• 2006.06a
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• pp.767-768
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• 2006

In this paper we propose a new routing protocol, which takes residue energy of nodes into account in order to prevent node failures resulting from energy shortage. Our routing protocol examines the smallest value of node residue energy ($E_m$) from each of all possible routing paths and selects the path which has the largest value of $E_m$. We prove, through simulation, that our routing protocol extends the lifetime of nodes which have limited amount of energy, reducing chances of path replacement. It is also shown that our proposed protocol helps alleviate network performance degradation.

• Proceedings of the SAREK Conference
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• 2008.11a
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• pp.481-486
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• 2008

The building HVAC systems have very different qualities of performance and durability with the superintendent's ability for management and maintenance. The poor management of these systems finally lead to the shortening of the life expectancy and result in the increase of operating costs and energy consumptions due to low efficiencies. So it is essential to try to develop ways to adequately maintain and to use the building facilities efficiently in order to preserve earth environment and the limited resource. In this study, the LCC based numerical calculation package will be developed for the efficient maintenance plan and the determination of the reasonable time of repair or replacement of equipments.

• Journal of mucopolysaccharidosis and rare diseases
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• v.4 no.2
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• pp.37-41
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• 2018

Mucopolysaccharidosis III (MPS III, Sanfilippo syndrome) is a rare autosomal recessive disease caused by a deficiency of one of four enzymes involved in the degradation of glycosaminoglycan (GAG). The resultant cellular accumulation of GAG causes various clinical manifestations. MPS III is divided into four subtypes depending on the deficient enzyme. All the subtypes show similar clinical features and are characterized by progressive degeneration of the central nervous system. A number of genetic and biochemical diagnostic methods have been developed. However, there is no effective therapy available for any form of MPS III, with treatment currently limited to clinical management of neurological symptoms. Main purpose of the treatment for MPS III is to prevent neurologic deterioration. Because conventional intravenous enzyme replacement therapy (ERT) has a limitation due to inability to cross the blood-brain barrier, several innovative therapeutic approaches for MPS III are being developed. This review covers the currently developing new therapeutic options for MPS III including high dose ERT, substrate reduction therapy, intrathecal or intraventricular ERT, fusion protein delivery using bioengineering technology, and gene therapy.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.34 no.5
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• pp.271-282
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• 2021

The internet of things (IoT) technology is a key component for the advent of 4^th industrial revolution, which is the network of home appliances, infrastructures, and vehicles to remotely investigate these systems. For the operation of compact IoT devices, batteries are widely used as electric power, and the limited lifetime of batteries inevitably leads to periodic replacement. Magneto-mechano-electric (MME) generators may be alternatives to batteries inside the IoT devices by converting stray magnetic field into electric energy, since we are always surrounded by ambient alternating current (AC) magnetic fields induced from electric power transmission lines everywhere. This article reviews the recent domestic research progress in high-performance MME generators and their application field for IoT and electronic devices.

• Journal of the Semiconductor & Display Technology
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• v.21 no.4
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• pp.86-91
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• 2022

Cache bypassing is a scheme to prevent unnecessary cache blocks from occupying the capacity of the cache for avoiding cache contamination. This method is introduced to alleviate the problems of non-volatile memories (NVMs)-based memory system. However, the prior works have been studied without considering wear-out attack. Malicious writing to a small area in NVMs leads to the failure of the system due to the limited write endurance of NVMs. This paper proposes a novel scheme to prolong the lifetime with higher resistance for the wear-out attack. First, the memory reference pattern is found by modified reuse distance calculation for each cache block. If a cache block is determined as the target of the attack, it is forwarded to higher level cache or main memory without updating the NVM-based cache. The experimental results show that the write endurance is improved by 14% on average and 36% on maximum.

• Journal of the Semiconductor & Display Technology
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• v.21 no.3
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• pp.1-6
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• 2022

Modern computer systems usually have special hardware for operations used in deep learning workload even edge computing environment. Non-volatile memories (NVMs) have been considered for alternative memory storage because they consume little static energy and occupy small area. However, there is a problem for NVMs to be directly adopted. An NVM cell has limited write endurance, so that the lifetime of NVM-based memory system is much shorter than that of conventional memory system. To overcome this problem for the deep learning system, this paper proposes a novel method to extend the lifetime based on the analysis of the deep learning workloads. If an incoming block has more than a predefined number of frequently used values, the cacheline is defined as write friendly block. During the victim selection, the cacheline has lower possibility to be chosen as victim. The experimental results show that the lifetime is increased by about 50% and energy consumption is decreased by 3% with a little performance hurt.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.15 no.2
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• pp.81-91
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• 1993

Arthrosis of the temporomandibular joint is defined as a disease of a joint with chief complaint of pain, clicking, limited jaw movements. Generally, most patients with the temporomandibular arthrosis can be treated conservatively with muscle relaxation therapy combined with mandibular repositioning prostheses, followed by occlusal equilibration, restorative dentistry and/or orthodontics, and many other forms of treatment. In case prior nonsurgical treatment proved to be ineffective or the disease is chronic and severe, surgical operation is recommended. For patients with arthrosis of the temporomandibular joint, only discectomy as therapeutic method of the surgical treatment should not be applied and the removed articular disc of the temporomandibular joint should be replaced. Allograft such as Proplast-Teflon, Silastic, etc have been used as replacements of removed articular disc. However, these allograft materials have caused complications such as inflammatory changes, foreign body reactions. As a result, a replacement material which is autogenous, space occupying, easy to harvest and less inflammatory change has been developed. Auricular cartilage with perichondrium satisfies many of these requirements. The apparent advantages of autogenous auricular cartilage as an interpositional graft after a discectomy are as follows, (1) the form of the external ear corresponds to joint morphology, (2) a graft of adequate size can be harvested, (3) the form of the external ear remains unchanged after surgery, (4) the graft can be obtained adjacent to the surgical site, (5) biologically acceptable material is used, (6) the additional expense of allogenic graft is avoided. Because we considered autogenous auricular cartilage as a good replacement material, removed articular disc has been replaced with fresh autogenous auricular cartilage in the case of three patients. The result of the treatment is favorable, and the cases being presented here.

• Journal of Labour Economics
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• v.39 no.2
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• pp.113-139
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• 2016

The purpose of this study is to establish evaluation model that can explain marginal effects of baseball players of Korean Baseball Organization (KBO) on their team winnings in terms of productivity. We proposed econometric model with using variables that are provided from official homepage of KBO to overcome the complexity of mainly used productivity index: wins above replacement (WAR). Also, compare to the previous studies such as Scully(1974) or Krautmann(1999) that using limited indices of baseball stats, this study included 61 indices that are provided from official homepage of KBO. We estimated regression based WAR(RBWAR) by conducting panel regression with each team's statistics data of 2002 to 2014. As a results, RBWAR shows 0.869 correlation coefficient for batters and 0.882 for pitchers with WAR in 2014 that can be concluded that two indices shows similar results. From the results of estimation, we analyze the relationship between productivity and actual contract of free agent players in 2015 and it showed that teams have contracted reasonably.

• Journal of Biomedical Engineering Research
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• v.26 no.5
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• pp.337-341
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• 2005

Blood pulsation has been reported to have an advantageous effect on extracorporeal blood circulation. However, the study of pulsatile blood flow in renal replacement therapy is very limited. The in-vitro experimental results of pulsatile blood flow on ultrafiltration, when compared with the conventional roller pump, are described in this paper. Methods: Blood flow rate (QB) and transmembrane pressure (TMP) were considered as regulating factors that have an influence on ultrafiltration. Experiments were performed under the condition of equal TMP and OB in both pulsatile and roller pump groups, Several kinds of hollow fiber dialyzers were tested using distilled water containing chemicals as a blood substitute. Mean TMP (mTMP) varied from 10 to 90mmHg while the QB was 200ml/min. Results: Ultrafiltration rate (QUF) was found to be linearly proportional to TMP, whereas QB had little influence on QUF. In addition, QUF was higher in the pulsatile group than the roller pump group at the identical TMP. Conclusion: In the controlled test, QUF increased solely as a consequence of blood pulsation, which implies that the pulse frequency represents an additional and important clinical variable during renal replacement therapy.