• KIPS Transactions on Computer and Communication Systems
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• v.6 no.1
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• pp.43-50
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• 2017

Use-After-Free security problem is rapidly growing in popularity, especially for attacking web browser, operating system kernel, local software. This security weakness is difficult to detect by conventional methods. And if local system or software has this security weakness, it cause internal security problem. In this paper, we study ways to remove this security weakness in software development by summarize the cause of the Use-After-Free security weakness and suggest ways to remove them.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.27 no.4
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• pp.803-810
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• 2017

Recently, social security problems have been caused by the development of the software industry, and a variety of automation techniques have been used to verify software stability. In this paper, we propose a method of automatically detecting a use-after-free vulnerability on Windows system calls using dynamic symbolic execution, one of the software testing methods. First, a static analysis based pattern search is performed to select a target point. Based on the detected pattern points, we apply an induced path search technique that blocks branching to areas outside of interest. Through this, we overcome limitations of existing dynamic symbolic performance technology and verify whether vulnerability exists at actual target point. As a result of applying the proposed method to the Windows system call, it is confirmed that the use-after-free vulnerability, which had previously to be manually analyzed, can be detected by the proposed automation technique.

• Journal of Trauma and Injury
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• v.20 no.2
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• pp.119-124
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• 2007

Purpose: Management of the soft tissue defect in the lower extremity caused by trauma has always been difficult. Coverage with local and free muscle flaps after complete surgical excision of necrotic soft tissue and bone is a major strategy for treatment. There is no doubt that muscle provides a good blood supply, thus improving bone healing and increasing resistance to bacterial inoculation. However, accompanying problems are seen in cases with shallow dead space. This research was conducted to assess the efficacy of raising anterolateral thigh flaps and transferring them to the defect after complete debridement of non-viable, infected, and scar tissue as an alternative way to use local or free muscle flaps. Methods: From March 2005 to October 2007, 18 cases of soft tissue defect on lower extremities were re-surfaced with an anterolateral thigh perforator free flap. Results: The follow-up period ranged from 1 to 31 months with a mean of 15.9 months. All flaps survived completely. Satisfactory aesthetic and functional results were achieved. Under a two-point discrimination test, 13 patients had sensory recovery from 11 mm to 20 mm after 6 months postoperatively. Conclusion: Reconstruction of the lower extremity with anterolateral thigh perforator free flaps after appropriate debridement is a good alternative way to use local or free muscle flaps.

• Journal of Chest Surgery
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• v.24 no.12
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• pp.1232-1237
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• 1991

The cervical esophageal stricture has various surgical modalities and difficulties in reconstruction. We had experienced a case of successful reconstruction of the cervical esophageal restenosis using the free jejunal graft, on 30 year old man had had esophageal stricture after ingestion of lye. He had undergone colon interposition[esophagocologastrostomy] with left colon feeding gastrostomy. But restenosis was occurred just above of the cervical esophagocolostomy site several times of balloon dilatation were failed. So, we decided to use of the free jejunal graft. The free jejunal graft was isolated about 15cm length with it`s vascular arcades. The graft was irrigated with the mixed solution as isotonic saline, heparin and papaverine chloride. The artery of graft was anastomosed to the branch of the external carotid artery in end to side with continuous sutures of the 8.0 Prolene. The vein of the graft was anastomosed to the branch of the anterior facial vein in end to end with continuous sutures of the 8.0 prolene. Postoperative course was uneventful and the patient was discharged after removal of the tracheostomy cannula and gastrostomy tube.

• The Korean Journal of Zoology
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• v.4 no.2
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• pp.13-19
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• 1961

Free amino acids at five different developemntal stages (Gastrulation-Hatching -out stage) of Hynobius leechi BOULENGER were analyzed qualitatively by the use of paper paitition chromatography. It was found that the number of free amino acids increased as the development proceeded. The free amino acids identified at each stages are as follows : Gastrulation stage : Alaninie, Aspartic acid, Glutamin acid, Histidine, Methionine. Neural plate formation stage : Alanine , Aspartic acid, Glutamic acid, Glycine, Histidine, MEthionine, Phenylalanine, Proline, Serine, Trypotophan. Middle tail-bud stage : Alanine, Arginine, Asparagine,Aspartic acid, Citrulline, Glutamic acid, Glycine, Histidie,Hydroxyproline, Proline, Leucine, Methionine, Ornithine, Phenylalanine, Serine, Threonine, Tryptophan. Late tail-bud stage : Alanine, Arginine, Asparagine, Aspartic acid, Citrulline, Glutamic acid. Glycine, Histidine, Hydroxyproline, Leucine, Methionine, Ornithine, Phenylalanine, Proline, Serine, Threonine, Tryptophan, Valine. Hatching -out stage : the same with the late tail-bud stage. It seems probable that the metabolic systems of amino acids before and after the middle tail-bud stage are quite different from each other. Before the middle tail=-bud stage, the reaction system of amino acids is thought not to be completed while after that stage the system has been completed , because in the former period of the development , the number of freeamino acids increased rapidly with the development , and after that stage, there is practically no change in the number of free amino acids.

• Journal of the Microelectronics and Packaging Society
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• v.22 no.3
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• pp.1-7
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• 2015

In this study, properties of Pb-free solders for automotive electronics parts were discussed. Lead-free solders for electronics became important after RoHS (Restriction of the use of certain Hazardous Substances) to avoid environmental pollution. Also the growing electronic rate in automotive parts and ELV (End-of Life Vehicles) make Pb-free solder for automotive electronics to be inevitable trend. Definitely, Pb-free solder for automotive electronics should have good wettability, basic strength, but need more reliability than other solders, since it has harsh condition like high temperature, humidity and engine vibration. Thus, shear strength test, thermal shock, drop test and many others are needed to ensure the high reliability. This study describes the properties and requirements of Pb-free solders for automotive electronics.

• Archives of Plastic Surgery
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• v.33 no.2
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• pp.245-248
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• 2006

Besides gastric pull-up or colonic interposition, microvascular technique in esophageal reconstruction has been approved reliable methods. When free intestinal transfer is considered, jejunal free flap is commonly used. We treated the patient who had undergone reconstruction with a right colon interposition and suffered from inability of swallowing because of stricture and necrosis of the interposed flap. Although we have planned jejunal free transfer, we couldn't use jejunum due to adhesion by previous gastrojejunostomy and colon interposition. Salvage procedure with microvascualr free left colon flap was executed successfully. After 9 month follow-up, the patient was able to consume a normal diet.

• Archives of Reconstructive Microsurgery
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• v.10 no.2
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• pp.105-110
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• 2001

Breast reconstruction is an aesthetically critical procedure and should be peformed to match the opposite breast in shape, contour, and position. Many methods were introduced to reconstruct the breast with autogenous tissue. But, free tissue transfer for breast reconstruction has become common method. The transverse rectus abdominis myocutaneous flap technique has been a widely accepted method of breast reconstruction after mastectomy, since the first introduction of free abdominoplasty flap in 1979. In breast reconstruction with a free flap the selection of suitable recipient vessels remains one of the most critical decision for surgeon. The most common recipient site for free flap breast reconstruction is the axillar system. But, the use of the axillary system as a recipient site limits flap movement and flexibility in breast shaping. The use of internal mammary vessels as a recipient site be able to achieve ideal breast symmetry, but that technique require the rib resection. The selection of suitable recipient vessels is most important for successful free tissue transfer. We have performed breast reconstruction with TRAM flaps anastomozed to the internal mammary vessel perforator. We came to the conclusion that this vessel perforator is useful as a recipient site in cases of immediate breast reconstruction with free TRAM flap.

• Archives of Plastic Surgery
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• v.36 no.5
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• pp.670-673
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• 2009

Purpose: Epidural abscesses and subdural empyemas after craniotomy are uncommon, potentially lethal, complications of neurosurgery. Patients with these complications may be difficult to manage and dural reconstruction in these patients are challenging. Methods: A 28 - year - old female patient showed recurrent intracranial infection after craniotomy for evacuation of a arachnoid cyst and subdural hematoma. Despite prolonged systemic antibiotic administration and a debridement of the subdural space, infection persisted, as evidenced by persistent fever, an elevated WBC count, CSF leakage, low CSF glucose level, and purulent wound discharge. The authors removed the previously applied lyophilized dura and transferred free omental flap to reconstruct the dura, obliterate the cyst and cover the cerebral hemisphere in the craniotomy defect. Microvascular anastomosis was between gastroepiploic and superficial temporal vessels. Results: The postoperative course was uneventful and flap survival was excellent. The infection - resistant omental tissue allowed sufficient blood circulation and dead space control. The patient was discharged 1 month after surgery and wound discharge or recurrence was absent during 13 months of follow up periods. Conclusion: The use of vascularized free omentum proved useful in cases of intractable cranial wound infection and cerebrospinal fluid leakages.

• Korean Institute of Interior Design Journal
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• no.41
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• pp.80-87
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• 2003

This paper attempts to examine the historical changes, the characteristics and the role of free-standing wall from the viewpoint of architectural composition. After modern times the wall gets free of structure and the view of formative art changes, which become a basis of the conscious use of free-standing wall. It plays a role of getting territoriality and placeness, by defining the space at the external territory and it is used as apparatus which controls circulation and orientation externally At the same time it is used as an instrument to blur the border to make mutual intersection and plays a role of introducing and controling the environment. The free-standing wall controls the architectural form to emphasize plasticity and is used to define a geometrical frame and maintain the urban context. In view of the results so far achieved, the free-standing wall is used as general vocabulary of modulating the border of space and the architectural form since modern architecture.