• Title/Summary/Keyword: bang-bang principle

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The Cytotoxic Limonoid From the Fruits of Melia Toosendan (천련자로부터 분리한 Limonoid 성분의 세포독성)

  • Km, Young-Ho;Hwang, Bang-Yeon;Kim, Se-Eun;Kim, Hwan-Mook;Oh, Goo-Taeg;Ro, Jai-Seup;Lee, Kyong-Soon;Lee, Jung-Joon
    • YAKHAK HOEJI
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    • v.38 no.1
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    • pp.6-11
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    • 1994
  • The MeOH extract of the fruits of Melia toosendan was selected for futher study by its cytotoxicity and effect on the human breast cancer cell line, MCF-7. The active principle obtained by activity guided fractionation followed by purification gave rise to a needle crystal. The structure was deduced by employing NMR and was determined to be identical with 28-deacetyl sendanin by comparison with published data. This compound induced morphological change of MCF-7 to be rounded with tubule at concentrations between $50\;{\mu}g/ml$ and $0.025\;{\mu}g/ml$. This compound, however, showed strong cytotoxic effect on Hepalclc7 and HepG2, and their $GI_{50}$ on the hepatoma cell lines were $0.238\;{\mu}g/ml$ and $0.805\;{\mu}g/ml$, respectively. Its effect on lymphocyte of mouse was stronger than hepatoma cell lines, and their $ED_{50}$ of polyclonal antibody response was $0.011\;{\mu}g/ml$, and $ED_{50}$ of cell viability was $0.039\;{\mu}g/ml$.

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A Study on the Kinematics of Ocean Waves by Gravity Wave Theory and Stream Function Method (해양파(海洋波)의 운동학(運動學)에 대한 중력파이론(重力波理論)과 Steam Function Method의 비교연구(比較硏究))

  • Y.K.,Bang;I.H.,Chang;H.S.,Choi
    • Bulletin of the Society of Naval Architects of Korea
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    • v.19 no.2
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    • pp.33-39
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    • 1982
  • It is one of the basic problems of naval architecture and ocean engineering how to describe the wave kinematics normally under the assumption of an ideal fluid. At present, there are many wave theories available for design purposes. These can be classified into two groups: One is the analytic theory and the other is the numerical theory. This paper briefly introduces the stream function method of R.G. Dean which belongs to the latter group and shows its numerical evaluations exemplified for two cases: One is applied to observed waves and the other is for design waves. In the former case, the wave profiles are calculated by the stream function method and compared with those of the observed waves and also with the results of R.G. Dean. They show good agreement. In the latter case, the wave kinematics and wave loads on a column of diameter 1m are calculated by the stream function method and these are compared with those resulted from the 5th-order gravity wave theory. As a result of comparison the values by the stream function method are slightly larger than those by the 5th-order gravity wave theory but the difference are negligible. From this it is concluded that the stream function method is very useful. And as characteristics of the numerical theories, the stream function method of R.G. Dean can be easily extended to the higher order terms and can include easily the current velocity and the pressure distribution on the free surface. In addition, when the data of observed wave profile are given, this method can reproduced the observed wave profile as closely as possible so that this method seems to describe the ocean wave more realistically. And from standpoint of a mathematical principle the stream function method exactly satisfies the kinematic free-surface boundary condition.

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A Comparative Study on Chesangshi and Joobyingshi of Binhohmaekhak and Maekshinjang of Kyungakjeonsuh ("빈호맥학(瀕湖脈學)"의 "체상시(體狀詩)", "주병시(主病詩)"와 "경악전서(景岳全書)" 중 "맥신장(脈神章)"의 정맥16부(正脈16部) 비교연구)

  • Lee, Jin-Cheoul;Park, Sang-Kyun;Bang, Jung-Kyun
    • Journal of Korean Medical classics
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    • v.25 no.2
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    • pp.107-123
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    • 2012
  • Objective : Kyungakjeonsuh(景岳全書) is a general medical book written by Jang, Gaebin(張介賓). In this book, Maekshinjang(脈神章) written about Maek, has three parts: (1)Naegyung maekui(內經脈義); (2)Tongiljamaekui(通一子脈義); (3)various views of Maek according to different schools. Among these three parts, Tongiljamaekui is Jang Gaebin's view on Maek, which is also called Jungmaek 16parts(正脈16部), a summary of the existing theory of Maek. Method : The contents of this paper are Chesangshi(體狀詩), literally means Body and Condition and Joobyingshi(主病詩), literally means Major Ailment of Binhohmaekhak(瀕湖脈學), and Jungmaek 16parts of Maekshinjang, and the result of examination through comparing them. Result : The purpose of this paper is to indicate the characters of the theories of Maek written in Kyungakjeonsuh through comparing Jungmaek 16 parts and Binhohmaekhak written by Doctor Yi, Shijin(李時珍), which is the basic study of Maek. Conclusion : The major study sectors of Kyungakjeonsuh are (1) the summary of the existing Maeksang as 16 Maeks, (2) the new definition of Huh Maek(虛脈) and Shil Maek(實脈) and (3) the utilization of eight-class-demonstration(8綱辨證) with 6 Maeks (浮, 沈, 遲, 數, 虛, 實) as a general principle.

VMProtect Operation Principle Analysis and Automatic Deobfuscation Implementation (VMProtect 동작원리 분석 및 자동 역난독화 구현)

  • Bang, Cheol-ho;Suk, Jae Hyuk;Lee, Sang-jin
    • Journal of the Korea Institute of Information Security & Cryptology
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    • v.30 no.4
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    • pp.605-616
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    • 2020
  • Obfuscation technology delays the analysis of a program by modifying internal logic such as data structure and control flow while maintaining the program's functionality. However, the application of such obfuscation technology to malicious code frequently occurs to reduce the detection rate of malware in antivirus software. The obfuscation technology applied to protect software intellectual property is applied to the malicious code in reverse, which not only lowers the detection rate of the malicious code but also makes it difficult to analyze and thus makes it difficult to identify the functionality of the malicious code. The study of reverse obfuscation techniques that can be closely restored should also continue. This paper analyzes the characteristics of obfuscated code with the option of Pack the Output File and Import Protection among detailed obfuscation technologies provided by VMProtect 3.4.0, a popular tool among commercial obfuscation tools. We present a de-obfuscation algorithm.

An Antibiotic against Bacillus amyloliquefaciens from Streptomyces sp. KM-48 (Streptomyces 속 KM-48 균주가 생성하는 Bacillus amyloliquefaciens 에 대한 항생물질)

  • Lee, Sang-Man;Song, Bang-Ho
    • Microbiology and Biotechnology Letters
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    • v.11 no.1
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    • pp.39-45
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    • 1983
  • One of Streptomyces sp. was screened as an antibiotic producing strain against Gram positive bacteria specifically from about one hundred Actinomycetes collections. The isolated KM-48 strain, indexed in our collection, was secreted an anbitiotic in nutrient broth culture. The active principle was extracted with acetone from the lyophilized solid of cultured filtrate. The nonadsorbed elute in aluminium oxide was isolated as a purified homogeneity which revealed a sing1e spot under ultra-violet beam on avicel thin layer chromatography. The isolated antibiotic was sensitive specifically against the Gram positive bacteria and fungi. About fifty percent inhibition of the control growth on Bacillus amyloliquefaciens was 18$\mu\textrm{g}$/$m\ell$. The antibiotic was lavile against thermotreatment and stabled in acidic condition remarkably. The KM-48 was identified as a similar strain to Streptomyces tsusimaensis on its morphological and cultural characteristics.

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A Study for the Necessity and Recognizing Usability of Recruit Education Curriculum for Security Personnel (민간경비원 신임교육과목 필요성 및 활용성 인식에 관한 연구)

  • Bang, Whan-Bog
    • Korean Security Journal
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    • no.17
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    • pp.195-220
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    • 2008
  • Various Kinds of social pathology and crimes that threaten our daily safety are on the increase in process of time as a result of the development of science and technology empty of moral sense, Value Confusions, apolaustic tendency, economic and social transformation recently. Moreover the effective provision of police service lies beyond the boundaries of the police organization. Therefore private security personnel have made an effort for safety and protection of group as well as an individual through the introduction of private security industry based on a benefit principle and private security industry is being become complexes utilizing technology as well as high-end devices through various international events. The field of private security industry in Korea is being extended rapidly with expansionism of society and public services but the quality improvement is declining. Furthermore the study of recruit education program for security personnel as the basis of quality improvement is insufficient compared with the study of police service. Consequently, this investigation is going to contribute to development of recruit education program for security personnel through the analysis about difference of each subject usability for education about electronic security and facility guard.

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Isolation of an Active Principle from Torilis Fructus and Its Pharmacological Activities

  • Lee, Eun-Bang;Cheon, Seon-Ah;Park, Seon-Kwan;Kim, Ra-Min;Lee, Dawei
    • Proceedings of the Korean Society of Applied Pharmacology
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    • 1998.11a
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    • pp.178-178
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    • 1998
  • We reported that the hexane fraction of Torilis Fructus have an anti-inflammatory and analgesic effect. Therefore, in order to isolate the active compound, the hexan fraction of Torilis Fructus was chromatographed on silica gel column. The subfraction of hexane fraction was crystallized as colorless stout needles. The chemical structure of this compound was verified to be torilin through m.p., UV, IR, GC-MS, and NMR spectral data. In pharmacological tests, torilin exhibited strong anticarrageenan activity at the dose of 90 and 270 mg/kg, p.o. in rats, and it had inhibitory effect on the vascular permeability at the dose of 30 and 90 mg/kg, p.o. in mice. Torilin showed potent inhibition of leucocyte emigration in CMC-pouch at the dose of 3 and 9 mg/rat, s.c. Torilin have the analgesic effect at the dose of 30, 90 and 270 mg/kg, p.o. in both of the acetic acid- and phenyl-p-benzoquinone-induced writhing syndrome. It also increased the pain threshold at the dose of 30, 90 and 270 mg/kg, p.o. in the tail pressure method and the Randall-Selitto method. Torilin did not show a hypothermic action at the dose of 30 and 90 mg/kg, p.o. in mice. The acute toxicity of torilin was very weak: the LD$\_$50/ value was more than 5000 mg/kg, p.o. and 2000 mg/kg, Lp. in mice. From the above mentioned results, it was suggested that torilin had potent anti-inflammatory and analgesic activities in animals.

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Legal System Change on Business Establishment and Management in Digital Era (디지털시대에 있어서 창업경영에 관한 법제도의 변화)

  • Song, In-Bang
    • Journal of Digital Convergence
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    • v.11 no.3
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    • pp.23-31
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    • 2013
  • In Korea, middle and small-sized company takes up an absolute majority of all businesses, and most of them are founded as a limited company. Yet, it is a type of business that fits a company of certain size, and its establishment process is complicated due to various reasons such as investor protection. It is also required to have strict organization structure based on the principle of separation of ownership and management. Accordingly, as the principles may undermine entrepreneur's will to start business, there has been dramatic change in legal system on business establishment and management since 2010. The changes include streamlined process at the foundation stage and digitalization of many regulations on business establishment and operation for more convenience in starting business. Also, new business types for small-sized companies were adopted, and freedom to select business name has been enhanced. The issue of non-par value stock has been allowed, and various types of stock have been adopted for more convenient financing, defense against hostile M&A, and easier business succession.

The Substance of Crisis and Alternative Proposal in Journalism (저널리즘 위기의 실체와 극복방안에 관한 연구)

  • Shon, Seok-Choon
    • Korean journal of communication and information
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    • v.36
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    • pp.42-77
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    • 2006
  • As a term 'Media Big Bang' will appear, the media is extending explosively. But actually it is appearing the paradoxical phenomenon which journalism meets a crisis. If the purpose of journalism is 'to provide people with the information they need to be free and self-governing', the crisis of Journalism directly brings about the result which damages audience welfare. Consequently the preceding task which defends the public good of journalism is accurately to get at the root of the substance which brings about the crisis of Journalism. In this paper, the principle and basic ethics of Journalism was theorized on the concept of truth and fairness, how about Korean journalism was answered to the standard is analyzed. With the result it was confirmed Korean journalism does not defend even truth and fairness about important agenda to be solved today. It was recognizes the substance which brings about the crisis of Journalism is 'the crisis of basic ethics', and was presented a an alternative proposal. It was introduced the research of 'Committee of Concerned Journalists' in the United States, and proposed the effort which is saved journalism with organic combination of Korean academic world and journalist' group.

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A Study on 『Shanghanlun』 through Interpretation of the Post-formula Instructions(方後注文) (방후주문(方後注文)의 해석을 통한 『상한론(傷寒論)』 연구(硏究))

  • Bang, Jung-Kyun
    • Journal of Korean Medical classics
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    • v.32 no.4
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    • pp.1-15
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    • 2019
  • Objectives : To broaden understanding of "Shanghanlun", this paper analyzes and interprets its Post-formula instructions(方後注文). Methods : From the contents of Post-formula instructions that follow formulas in "Shanghanlun", the effects, administration instructions, decocting methods are examined specifically. Based on annotators's interpretations, the author provides his understanding. Conclusions & Results : The treatment principle of sweat inducive formulas is 'to induce subtle sweating(微似汗)'. Meanwhile, in the case of Inner water and fluid retention(水飮內停), 'sweating(汗出)' is expressive of healing. Among the emetic formulas in the "Shanghanlun", the meaning of 'vomiting(得吐者)' in the descriptions of Zhizichitang(梔子豉湯), is that the stagnated heat in the chest area has been relieved, letting the Qi communicate upwards. In terms of formula administration, besides the usual 2~3 times a day method, there is '頓服法' for immediate effects; three times within six hours application method in cases where the exterior symptoms are extremely severe or the stagnation of exterior pathogen is severe; 6 times a day or continuous application day and night regardless of frequency. In terms of decocting methods, there is '再煎法' to have the formula's effects not be biased or too strong; the decocting method of Dahuanghuanglianxiexīntang where the formula is brewed momentarily in order to cool the immaterial pathogenic heat. Moreover, when there is disease in the chest, Dahuang is brewed first to soften its effects. When there is disease in the abdomen area, Dahuang is added later to quicken its effects. In the case of Guizhirenshentang, to maximize the effect of Guizhi, it was suggested that Guizhi is added later.