• Title/Summary/Keyword: Circumvention

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Crop Injury (Growth Inhibition) Induced by Herbicides and Remedy to Reduce It (제초제(除草劑) 약해발생(藥害發生) 양상(樣相)과 경감대책(輕減對策))

  • Kim, K.U.
    • Korean Journal of Weed Science
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    • v.12 no.3
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    • pp.261-270
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    • 1992
  • Many herbicides that are applied at the soil before weed emergence inhibit plant growth soon after weed germination occurs. Plant growth has been known as an irreversible increase in size as a result of the processes of cell divison and cell enlargement. Herbicides can influence primary growth in which most new plant tissues emerges from meristmatic region by affecting either or both of these processes. Herbicides which have sites of action during interphase($G_1$, S, $G_2$) of cell cycle and cause a subsequent reduction in the observed frequency of mitotic figures can be classified as an inhibitor of mitotic entry. Those herbicides that affect the mitotic sequence(mitosis) by influencing the development of the spindle apparatus or by influencing new cell plate formation should be classified as causing disruption of the mitotic sequence. Sulfonylureas, imidazolinones, chloroacetamides and some others inhibit plant growth by inhibiting the entry of cell into mitosis. The carbamate herbicides asulam, carbetamide, chlorpropham and propham etc. reported to disrupt the mitotic sequence, especially affecting on spindle function, and the dinitroaniline herbicides trifluralin, nitralin, pendimethalin, dinitramine and oryzalin etc. reported to disrupt the mitotic sequence, particularly causing disappearence of microtubles from treated cells due to inhibition of polymerization process. An inhibition of cell enlargement can be made by membrane demage, metabolic changes within cells, or changes in processes necessary for cell yielding. Several herbicides such as diallate, triallate, alachlor, metolachlor and EPTC etc. reported to inhibit cell enlargement, while 2, 4-D has been known to disrupt cell enlargement. One potential danger inherent in the use of soil acting herbicides is that build-up of residues could occur from year to year. In practice, the sort of build-up that would be disastrous is unikely to occur for substances applied at the correct soil concentration. Crop injury caused by soil applied herbicides can be minimized by (1) following the guidance of safe use of herbicides, particularly correct dose at correct time in right crop, (2) by use of safeners which protect crops against injury without protecting any weed ; interactions between herbicides and safeners(antagonists) at target sites do occur probably from the following mechanisms (1) competition for binding site, (2) circumvention of the target site, and (3) compensation of target site, and another mechanism of safener action can be explained by enhancement of glutathione and glutathione related enzyme activity as shown in the protection of rice from pretilachlor injury by safener fenclorim, (3) development of herbicide resistant crops ; development of herbicide-resistant weed biotypes can be explained by either gene pool theory or selection theory which are two most accepted explanations, and on this basis it is likely to develop herbicide-resistant crops of commercial use. Carry-over problems do occur following repeated use of the same herbicide in an extended period of monocropping, and by errors in initial application which lead to accidental and irregular overdosing, and by climatic influence on rates of loss. These problems are usually related to the marked sensitivity of the particular crops to the specific herbicide residues, e.g. wheat/pronamide, barley/napropamid, sugarbeet/ chlorsulfuron, quinclorac/tomato. Relatively-short-residual product, succeeding culture of insensitive crop to specific herbicide, and greater reliance on postemergence herbicide treatments should be alternatives for farmer practices to prevent these problems.

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The Present Situation, Problems, Improving Plans about the Establishment and the Operation of a Medical Association - Mainly on the Violations of the Rules Regulating Medical Institute's Opening - (의료협동조합의 의료기관 개설·운영 현황과 문제점 및 개선방안 - 의료기관 개설기준 위반을 중심으로 -)

  • KIM, JOON RAE;BAEK, NAM BOK;LEE, YOON HAK
    • The Korean Society of Law and Medicine
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    • v.16 no.2
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    • pp.227-261
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    • 2015
  • Cooperative associations are established in order to enhance the rights and the interests of their members and serve the local communities, and actually do much for the local society. And among these, consumer cooperatives are spontaneously founded, particularly in the spirit of mutual help, in order to promote the common welfare of the members. Meanwhile, because the current medical law qualifys noncommercial corporation to open medical institution, consumer cooperative and noncommercial- corporation cooperative which are established under the Cooperative Act have the right to do. However, though cooperative association should be founded for common interests of the members who are weaker parties of society, it became rapidly to be abused as means of circumvention of law. Especially as National Health Insurance Corporation stepped up the investigation and the collection of unfair profits against the hospital owned by non-medical personnel who are unable to establish a medical institution, setting up medical institutions as a roundabout way to avoid the restricts dramatically increased in number. In this study, we are going to introduce the current dualised normative system regulating the establishment of a medical cooperative association, and find a way to improve the system and make up for the week points. And we will look though the present situation about medical cooperative association's opening, operating, and closing, and review the normative and systematic improving plans.

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Extraction and Taxonomy of Ransomware Features for Proactive Detection and Prevention (사전 탐지와 예방을 위한 랜섬웨어 특성 추출 및 분류)

  • Yoon-Cheol Hwang
    • Journal of Industrial Convergence
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    • v.21 no.9
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    • pp.41-48
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    • 2023
  • Recently, there has been a sharp increase in the damages caused by ransomware across various sectors of society, including individuals, businesses, and nations. Ransomware is a malicious software that infiltrates user computer systems, encrypts important files, and demands a ransom in exchange for restoring access to the files. Due to its diverse and sophisticated attack techniques, ransomware is more challenging to detect than other types of malware, and its impact is significant. Therefore, there is a critical need for accurate detection and mitigation methods. To achieve precise ransomware detection, an inference engine of a detection system must possess knowledge of ransomware features. In this paper, we propose a model to extract and classify the characteristics of ransomware for accurate detection of ransomware, calculate the similarity of the extracted characteristics, reduce the dimension of the characteristics, group the reduced characteristics, and classify the characteristics of ransomware into attack tools, inflow paths, installation files, command and control, executable files, acquisition rights, circumvention techniques, collected information, leakage techniques, and state changes of the target system. The classified characteristics were applied to the existing ransomware to prove the validity of the classification, and later, if the inference engine learned using this classification technique is installed in the detection system, most of the newly emerging and variant ransomware can be detected.