• 보존과학연구
• /
• s.11
• /
• pp.87-105
• /
• 1990

Chemical and micro morphological changes of archaeological waterlogged woods from shipwrecked materials in marine situations were investigated which were submerged in seabed for over 900 years. Tested Wood species were Pinusdensiflora, Zelkova serrata, Quercus acutissima and Camellia japonica. The obtained results were summarized as follows; Chemical analysis showed that lignin content was increased, whereas the amout of holocellulose was heavily decreased in the degraded archaeological lwoods(DAW), when compared to the recent woods. The amount of alkalineextractives in the DAW was extremley high. IR spectra showed that disappearance of absortion band at $1,730㎝^-1$ intensity increase at 1,600, 1,500 and $1,270㎝^-1$ and the emergence of single band around $1,050㎝^-1$.Microscopic investigation showed that cell wall of latewood tracheids and fiber in the DAW were severely degraded while, early wood tracheids less degraded. Degradation in the cell wall was mainley occurred in $S_2$layer, while the middle lamella was the least degraded. The micro morphological characteristics of DAW were separation of secondary wall from middle lamella, cavities aligned with micro fibril angle in $S_2$layer and granular appearance of secondary wall by the bacterial attack.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.15 no.5
• /
• pp.3159-3168
• /
• 2014

Interevent Time Definition(IETD) is essential in CSOs(Combined Sewer Overflows) tank design for the treatment of non-point source pollution. However, existent rainfall analysis can not calculate total amout of non-point source pollution. For deviding continuous rainfall events, therre are several IETD calculating methods. In this research, After calculate IETD by existents methods, problem of results is identified as existents method. To supplement these problems, new method using exponential decay function is suggested. The confidence range of ${\lambda}$ is estimated.

• Journal of the Korea Institute of Information Security & Cryptology
• /
• v.23 no.4
• /
• pp.767-779
• /
• 2013

A field of privacy protection lacks statistical information about the current status, compared to other fields. On top of that, since it has not been classified as a concrete separate field, the related survey is only conducted as a part of such concrete areas. Furthermore, this trend of being regarded as a part of fields such as informatization, information protection and law will continue in the near future. In this paper, a novel and practical way for collecting and storing a big amout of data from 110,000 privacy policies by data controller is proposed and the real analysis results is also shown. The proposed method can save time and cost compared with the traditional survey-based method while maintaining or even advancing the accuracy of results and speediness of process. The collected big personal data can be used to set up various kinds of statistical models and they will play an important role as a breakthrough of observing the present status of privacy information protection policy. The big data concept is incorporated into the privacy protection and we can observe the method and some results throughout the paper.

• The Journal of the Institute of Internet, Broadcasting and Communication
• /
• v.19 no.5
• /
• pp.229-238
• /
• 2019

Before the scholarship loan system was implemented at the Korea Scholarship Foundation, the government's role was strengthened by the direct lending of student funds to banks and other financial institutions. However, the low repayment performance of student loans has raised concerns over the future of student loans and the government's financial burden. Moreover, since student loans are repaid even after graduating from college to support low-income families, it is highly unlikely that the repayment rate of student loans will improve unless the employment rate and income level of the borrower improve. In this paper, the final visualization graph is presented of the repayment amount of the student loan through the collection, storage, processing and analysis phase in the Big Data-based system. This could be the basis for visually checking the amount of student loans to come up with various ways to reduce the burden on the current student loan system.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
• /
• v.25 no.4
• /
• pp.324-329
• /
• 1999

The facial esthetics are much affected by nasal changes due to especially its central position in relation to facial outline and so appropriately evaluated should be the functional and esthetic aspects of the nose associated with the facial appearance. Generally, a maxillary surgical movement is known to induce the changes of nasolabial morphology secondary to the skeletal repositioning accompanied by muscular retraction. These changes can be desirable or undesirable to individuals according to the direction and amount of maxillary repositioning. We investigated the surgical changes of bony maxilla and its effects to nasal morphology through the analysis of the lateral cephalogram in the Le Fort I osteotomy. Subjects were 10 patients(male 2, female 8, mean age 22.3 years) and cephalograms were obtained 2 weeks before surgery(T1) and 6 months after surgery(T2). The surgical maxillary movement was identified through the horizontal and vertical repositioning of point A. Soft-tissue analysis of the nasal profile was performed employing two angles: nasal tip projection(NTP), columellar angle(CA). Also, alar base width(ABW) was assessed directly on the patients with a slide gauge. The results were as follows; 1. Both anterior and superior movement above 2mm of maxilla rotated up nasal tip above 1mm. Either anterior or superior movement above 2mm of maxilla made prediction of the amount & direction of NTP changes difficult. Especially, a correlation between horizontal movement of maxilla and NTP rotated-up was P<0.01. 2. Both much highly anterior and superior movement of maxilla is accompanied by more CA increase than either highly. Especially, the correlation between horizontal movement of maxilla and CA change was P<0.05. 3. Anterior and/or superior movement of maxilla was accompanied by the unpredictable ABW widening. 4. The amount of changes of NTP, CA, and ABW is not in direct proportion to amout of anterior and/or superior movement of maxilla. 5. Nasal morphologic changes following Le Fort I osteotomy are affacted by not merely bony repositioning but other multiple factors.