• Journal of Chest Surgery
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• v.41 no.5
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• pp.550-562
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• 2008

Background: We attempted to reproduce a previously reported method that is known to be effective for decellularization, and we sought to find the optimal condition for decellularization by introducing some modifications to this method. Material and Method: Porcine semilunar valves, arterial walls and pericardium were processed for decellularization with using a variety of combinations and concentrations of decellularizing agents under different conditions of temperature, osmolarity and incubation time. The degree of decellularization and the preservation of the extracellular matrix were evaluated by staining with hematoxylin and eosin and with alpha-Gal and DAPI in some of the decellularized tissues. Result: Decellularization was achieved in the specimens that were treated with sodium deoxycholate, sodium dodesyl sulfate, Triton X-100 and sodium dodesyl sulfate with Triton X-100 as single-step methods, and this was also achieved in the specimens that were treated with hypotonic solution ${\rightarrow}$ Triton X-100 ${\rightarrow}$ sodium dodesyl sulfate, sodium deoxycholate ${\rightarrow}$ hypotonic solution ${\rightarrow}$ sodium dodesyl sulfate, and hypotonic solution sodium dodesyl sulfate as multi-step methods. Conclusion: Considering the number and the amount of the chemicals that were used, the incubation time and the degree of damage to the extracellular matrix, a single-step method with sodium dodesyl sulfate and Triton X-100 and a multi-step method with hypotonic solution followed by sodium dodesyl sulfate were both relatively optimal methods for decellularization in this study.

• Journal of Chest Surgery
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• v.41 no.6
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• pp.679-686
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• 2008

Background: Cellular remnants in the bioprosthetic heart valve are known to be related to a host's immunologic response and they can form the nidus for calcification. The extracellular matrix of the decellularized valve tissue can also be used as a biological scaffold for cell attachment, endothelialization and tissue reconstitution. Thus, decellularization is the most important part in making a bioprosthetic valve and biological caffold. Many protocols and agents have been suggested for decellularization, yet there ave been few reports about the effect of a treatment with hypotonic solution prior to chemical or enzymatic treatment. This study investigated the effect of a treatment with hypotonic solution and the appropriate environments such as temperature, the treatment duration and the concentration of sodium dodecylsulfate (SDS) for achieving proper decellularization. Material and Method: Porcine aortic valves were decellularized with odium dodecylsulfate at various concentrations (0.25%, 0.5%), time durations (6, 12, 24 hours) and temperatures ($4^{\circ}C$, $20^{\circ}C$)(Group B). Same the number of porcine aortic valves (group A) was treated with hypotonic solution prior to SDS treatment at the same conditions. The duration of exposure to the hypotonic solution was 4, 7 and 14 hours and he temperature was $4^{\circ}C$ and $20^{\circ}C$, respectively. The degree of decellularization was analyzed by performing hematoxylin and eosin staining. Result: There were no differences in the degree of decellularization between the two concentrations (0.25% 0.5%) of SDS. Twenty four hours treatment with SDS revealed the best decellularization effect for both roups A and B at the temperature of $4^{\circ}C$, but there was no differences between the roups at $20^{\circ}C$. Treatment with hypotonic solution (group A) showed a better ecellularization effect at all the matched conditions. Fourteen hours treatment at $4^{\circ}C$ ith ypotonic solution prior to 80S treatment revealed the best decellularization effect. The treatment with hypotonic solution at $20^{\circ}C$ revealed a good decellularization effect, but his showed significant extracellular matrix destruction. Conclusion: The exposure of porcine heart valves to hypotonic solution prior to SDS treatment is highly effective for achieving decellularization. Osmotic treatment with hypotonic solution should be considered or achieving decellularization of porcine aortic valves. Further study should be carried out to see whether the treatment with hypotonic solution could reduce the exposure duration and concentration of chemical detergents, and also to evaluate how the structure of the extracellular matrix of the porcine valve is affected by the exposure to hypotonic solution.

• KDI Journal of Economic Policy
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• v.16 no.1
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• pp.195-216
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• 1994

탈세(脫稅)의 규모추정(規模推定)을 위해서는 우선 과세표준의 누락정도를 추정해야 한다. 본 연구에서는 1987년과 1988년 도시가계조사 테이프를 이용하여 소득(所得)-지출추계방법(支出推計方法)에 의해 탈루소득(脫漏所得)이 전체소득(全體所得)에서 차지하는 비중을 추정하였다. 그 결과 1987, 1988년 두 해의 탈루소득(脫漏所得)의 규모는 전체 GNP의 약 15%인 것으로 추정되었다. 다시 이렇게 추정된 탈루소득비율(脫漏所得比率)을 이용하여 소득세(所得稅)의 탈세규모(脫稅規模)를 추정하였으며, 그 규모가 전체소득세(全體所得稅)에서 차지하는 비중은 1987년에 10~11.3%, 1988년에는 8.7~9.8%에 달하는 것으로 추정된다. 한편 부가가치세(附加價値稅)의 과세표준인 민간소비지출(民間消費支出)의 탈루규모(脫漏規模)는 전체탈루소득(全體脫漏所得)과 거시민간소비함수(巨視民間消費函數)에 추정된 민간소비(民間消費)의 대(對)GNP탄력성을 이용하여 추정한 결과, 1987, 1988년 모두 10.5%인 것으로 추정되었다. 이에 따라 1987, 1988년의 부가가치세(附加價値稅)의 탈세규모(脫稅規模)는 10.5~16.5%에 달했던 것으로 추정된다.

• Journal of Internet Computing and Services
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• v.22 no.6
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• pp.51-57
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• 2021

If a company's actions to save or avoid taxes are judged to be tax evasion rather than legal tax action by the tax authorities, the company will not only pay tax but also non-tax costs such as damage to corporate image and stock price decline due to a series of tax evasion-related news articles. Therefore, this study measures the frequency of occurrence of tax evasion controversial keywords in internet news portal as a factor to measure the severity of the case, and analyzes the effect of the frequency of occurrence on corporate value. In the Korean stock market, we crawl related articles from internet news portal by using keywords that are controversial for tax evasion targeting top companies based on market capitalization, and generate a time series of the frequency of occurrence of keywords about tax evasion by company and analyze the effect of frequency of appearance on book value versus market capitalization. Through panel regression and impulse response analysis, it is analyzed that the frequency of appearance has a negative effect on the market capitalization and the effect gradually decreases until 12 months. This study examines whether the tax evasion issue affects the corporate value of Korean companies and suggests that it is necessary to take these influences into account when entrepreneurs set up tax-planning schemes.

• Korea Petroleum Association Journal
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• s.273
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• pp.30-33
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• 2009

• Journal of Chest Surgery
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• v.37 no.3
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• pp.220-227
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• 2004

The number of patients with coronary artery disease and peripheral vascular disease are increasing, and the need of small diameter vessel is also increasing. We developed small diameter artificial vessel and experimented in vivo. We got allogenic valve from mongrel dogs, and removed all cells from the allogenic valve. Then, we seeded autologous bone marrow cells onto the decellularized scaffold. After implantation of artificial vessel into the canine carotid artery, we performed angiography regularly. In case of vessel occlusion or at 8 weeks after operation, we euthanized dogs, and retrieved the implanted artificial vessels. Control vessels were all occluded except one (which developed aneurysmal dilatation). But autologous cell seeded vascular graft were patent by 4 weeks in one, by 6 in one and by 8 weeks in two. Histologic examination of patent vessel revealed similar structure to native artery. Tissue-engineered vascular graft manufactured with decellularized allogenic matrix and autologous bone marrow cells showed that tissue engineered graft had similar structure to native artery.

• 정보화사회
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• s.184
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• pp.44-47
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• 2007

새해부터는 프로그램저작권 침해행위에 대한 벌칙이 현행 3년 이하의 징역에서 5년 이하의 징역으로 강화된다. 특히, 개인정보보호에 관한 법률이 크게 강화될 예정으로 개인정보를 취급하는 통신사업자의 개인정보 관리.감독 기준이 대폭 강화될 전망이며, 청소년의 유해정보차단을 효율적으로 집행하기 위한 법도 새로 시행될 전망이다. 이밖에도 새해에는 기간통신사업자의 지분인수 시 정보통신부 장관의 인가를 받아야 하며, 무선국 시설자들은 전자파강도를 측정하는 의무가 부여되는 등 많은 부분에서 새로운 제도가 시행될 전망이다. 또, 국세청장이나 지방국세청장도 조세범칙사건의 조사에 필요한 경우에 통신 자료제공을 요청할 수 있도록 법적근거를 마련해 통신매체를 활용한 탈세행위가 새해에는 원천 차단될 전망이다.

• Digital Contents
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• no.11 s.138
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• pp.60-63
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• 2004

절반 이상이 초선의원인 17대 국회 첫 국정감사가 10월 22일을 끝으로 3주간의 일정을 사실상 모두 마감했다. 이번 국정감사에서 정보통신 부를 감사한 과학기술정보통신위원회는 ▲정보화촉진기금 관련자 추가 비리 문제 ▲KT 민영화 졸속 추진 및 탈세 의혹 등 몇가지 정치 쟁 점화가 될 수 있는 사안에 대한 감사를 펼쳐 여∙야간 긴장이 고조됐지만, 대부분 차분하게 진행돼 무리 없이 지나갔다. 3주간에 걸쳐 진행 된 17대 국회 국정감사에서 디지털콘텐츠와 관련된 사안들을 간략하게 정리했다.

• Vending industry
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• v.4 no.4 s.12
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• pp.48-53
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• 2004

담배자판기는 되는데 주류자판기는 왜 안 되나? 담배자판기의 경우 성인인증장치를 도입해 부분적인 로케이션이기는 하지만 합법화되어 있음에 비해 주류자판기는 여전히 설치 자체를 규제한 채 철옹성의 장벽을 구축하고 있다. 이러한 현실에서 산업계는 성인인증장치를 도입한 주류자판기는 이제 규제가 완화되어야 한다는 목소리가 높이고 있다. 주력기종인 음료자판기는 극도의 시장불황에 시달리고, 이를 대신할 마땅한 사업아이템을 찾기 힘든 현실에서 주류자판기로 시각이 집중되는 것은 어찌 보면 자연스러운 일이다. 성인인증 주류자판기 시장은 규제만 완화된다면 산업계의 숨통을 틔어 줄 유망아이템이라는 점에서 결코 포기할 수 없는 영역이다. 산업계는 성인인증 주류자판기의 규제완화의 명분을 강화하고, 적극적인 산업계 자율대책을 제시하며 규제완화에 총력을 기울여야 한다. 협회에서는 산업계의 규제완화에 대한 열망을 반영해 최근 재정경제부 소비세제과를 대상으로 하는 건의 작업을 진행했다. 성인인증장치 도입을 통해 청소년 보호, 탈세방지 등 과거 주류자판기가 가질 수 있었던 위해요인을 극소화하는 산업계 자율대책을 바탕으로, 건전하게 주류자판기가 유통될 수 있게 해달라는 게 건의안의 골자이다. 이 건의안은 앞으로 적극적으로 검토가 될 예정이지만, 여전히 관련부처에서는 주류자판기에 대한 부정적인 시각을 가지고 있다는 점이 넘어야 할 벽이다. 재정경제부 소비세제과는 성인인증장치를 도입해 청소년 보호를 하는 측면은 높게 평가하지만, 과연 주류 유통기기로서 주류자판기가 필요한 것인 가에 대한 부정적인 시각을 가지고 있다. 또한 주류정책 자체가 유통을 억제하는 방향으로 나아가고 있다는 점, 또 탈세 방지 등 세원관리에 대한 문제점을 들어 주류자판기 자체를 부정적으로 보고 있다. 이 모든 벽들을 극복하고 규제완화의 길을 가는 것은 쉽지가 않다. 하지만 시대가 변하고, 관련 기술은 첨단화되고 있는 데 규제가 만사인 정책으로 주류자판기를 보는 시각을 곤란하다. 산업계가 얼마든지 위해요인을 해결하겠다는 자세를 보이는 마당에 이를 묵살하는 행정만능주의적 자세는 결코 올바른 행정이라 할 수 없다. 오랜 시간이 걸려도 산업계는 강력한 의지를 가지고 성인인증 주류자판기의 생존권을 확보해야 한다. 협회에서는 재경부 이외에도 국세청, 규제개혁위원회 등을 통한 규제완화 작업을 지속적으로 진행해 나갈 계획이다. 금호 정책초점에서는 성인전용 주류자판기 규제완화에 대한 뜨거운 열망을 담아, 협회에서 재정경제부 소비세과에 건의했던 건의안의 세부내용을 게재했다.

• Journal of Urban Science
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• v.6 no.2
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• pp.35-47
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• 2017

Tax evasion is increasing, but efficiency of tax administration is evaluated as improving. This is because the taxation cost, which is a measure to judge the efficiency of the tax administration, does not consider the tax evasion effect at all. This method of estimating the cost of taxation is a dispute that neglects the role of taxation authorities in tax evasion. The existing study focuses on the development of a tax evasion model focused on maximizing the utility through the tax evasion of the taxpayer as the tax evasion approaches the individual 's deviant problem. However, this has the aspect of making the role of the tax authorities in tax evasion negative. This study empirically derived the optimal size of tax administration in Korea by using tax collection cost and tax cooperation cost. Also, it is meaningful to consider the role of the taxation authorities in tax evasion and to derive the optimal taxation cost model by estimating the decrease in tax evasion due to the taxation expenditure of the tax authorities. In order to derive the optimal size of tax administration in Korea, taxation cost and tax cooperation cost are derived by classifying tax officials. The optimal taxation cost model was derived by estimating the taxation expenditure related to tax evasion. This study is meaningful to make it possible to emphasize the role of tax authorities in studying future tax evasion by studying the effect of taxation expenditure on tax evasion.