蠶糞의 成分에 關한 硏究

주현규,박면용,김문주,민경찬 건국대학교 1974 學術誌 Vol.17 No.1

이온주입이 금속의 일함수에 미치는 영향(Ⅰ)

김현경,강석태,황정남,이철주,최대선,정병두 연세대학교 자연과학연구소 1984 學術論文集 Vol.13 No.-

이온 주입이 일함수 차이에 미치는 영향을 연구하기 위하여 낮은 에너지 이온 가속기, 전자총과 기타 일함수 차이를 측정하기 위한 장치를 설계, 제작하였다. 제작된 이온 가속기의 집속 특성은 이론적인 값과 일치하였다. 즉, 집속 렌즈의 확대율이 이론값은 2.0인데 비하여 1.2로 상당히 작은 값이었다. 또한 집속 렌즈의 전압 V_L과 추출 전압 V_e에 의한 집속 특성 역시 이론값과 매우 잘 일치하였다 . 제작된 장치를 사용하여 다결정 Cu와 Ni의 일함수 차이를 측정한 결과 0.45eV임을 알았다. 그리고 전자선을 이용하여 억제 전위차로 일함수를 측정할때 입사 전자의 반사율을 고려해야 함을 알았다. Low energy ion accelerator, electron gun, and apparatus for measuring work function difference are designed and constructed in order to study the effect of ion implantation on the work function. The focusing properties of accelerator is coincided with theoretical results; the magnification of Einzel lens is found to be 1.2, while theoretical value is 2.0, and the focal properties as a function of V_L/V_e are in good agreement with theory. Using these systems, the work function difference between polycrystalline Cu and Ni is found to be 0.45eV, and the experimental retarding potential plots indicate close agreement with the theoretical values modified by electron reflection.

유치열과 혼합치열기 어린이의 상악 절치부 외상

정주현,이제호,김성오,최병재 大韓小兒齒科學會 2004 大韓小兒齒科學會誌 Vol.31 No.2

현대인의 생활양식과 환경이 도시화 및 인공화되고 취미활동이 다양화됨에 따라 외상을 받을 수 있는 요인들을 증가하고, 특히 어린이 활동량이 많아져 외상의 기회가 잦아지고 있다. 어린이에서 외상이 발생하는 경우, 어린이의 일상적인 활동 뿐 아니라, 사회성 및 정서 발달에도 영향을 미칠 수 있으며, 그 보호자에게도 부정적인 영향을 미칠 수 있기에 외상의 발생 빈도를 줄이고 예방하는 것이 중요하다. 본 연구는 유지열과 혼합치열기에 발생하는 치아 외상을 예방하기 위한 기초 자료를 얻기 위하여, 특히 구강악안면부의 외상시 치아 외상을 가장 많이 받는 상악 유절치와 영구절치를 연구하기 위하여, 2002년 6월부터 2003년 5월까지 연세대학교 치과대학병원 소아치과에 내원한 유치열과 혼합치열기의 신환 8.799명중 상악 절치부 외상을 주소로 내원한 어린이 487명(남자 316명, 여자 171명)의 상악 절치 955개(유절치543개, 영구절치 412개)를 조사하여 다음과 같은 결과를 얻었다. 1. 상악 절치부 외상이 호발하는 나이는 유절치에서 1~3세, 영구절치에서 7세였으며 남자대 여자의 비율은 1.85:1이었다. 2. 상악 절치부 외상은 유절치와 영구절치 모두 오후 시간에 많이 발생하였으며, 유절치는 외상 장소로 집이 가장 많았고 (44.1%), 영구절치는 길에서 다치는 경우가 가장 많았다(17.5%). 3. 외상의 원인으로 유절치와 영구절치 모두 넘어져 다치는 경우가 가장 많았으며(39.8%, 12.9%), 다음으로 부딪히는 경우가 많았다(22.2%, 6.0%). 유절치에서는 다음으로 떨어져 다치는 경우, 교통사고, 폭력과 운동에 의한 외상 순이었으며, 영구절치에서는 폭력, 운동, 교통사고, 떨어져 다치는 순이었다. 4. 조사대상 어린이 1명당 유절치는 1.6개, 영구절치는 2.8개에 외상을 입었다. 5. 유절치와 영구절치 모두에서, 치관 파절 양상은 치수미노출 치관 파절이 많았고, 치주조직 외상 양상은 아탈구가 가장 많았다. 최근 어린이의 단체 생활이나 운동과 취미 활동에 참여하는 나이가 예전에 비하여 점차 낮아지고 있어, 이번 연구 결과와 같이, 외상이 발생하는 나이 역시 지속적으로 낮아질 수 있다. 나이에 따른 어린이의 외상을 받는 장소는 특별한 곳이 아닌, 집이나 학교와 같은 일상의 생활공간이기 때문에 단순한 주의만으로도 외상의 발생을 예방할 수 있을 것으로 사료된다. In children, change in lifestyles such as an increase in participation of physical activities has increased the chance of receiving an injury, harming the child and their parents. This study was carried out to give basic information of traumatic injuries to the upper anterior teeth which can be used in prevention of future complications that may arise. From June, 2002 to May, 2003, of the 8,799 children in their primary and mixed dentition visiting Department of Pediatric Dentistry, College of Dentistry, Yonsei University. 955 upper anterior teeth(primary 543, permanent 412) of 487 children(ma1e 316, female 171) with traumatic injures to the upper incisors were studied. The results were as follows: 1. Trauma to the primary teeth prevailed at the age of 1-3 and to the permanent teeth at the age of 7. The male to female ratio was 1.851. 2. Trauma to the upper incisors for both the primary and permanent teeth occurred in the afternoon. Primary teeth were injured most frequently in the home(44.1%) and the permanent teeth outdoors, in the street(l7.5%). 3. Both the primary and permanent teeth were most injured by fall-down injuries(39.8%, 12.9%), and next were collisions(22.2%, 6.0%) :For the primary teeth, high fall, traffic accident, violence and sports are next in order, and for the permanent teeth, violence, sorts, traffic accidents were next. 4. Average number of 1.6 primary teeth and 2.8 permanent teeth were injured with the right central incisor most prevailing. 5. Crown fracture without pulpal exposure and subluxation injures were highest in frequency in both the primary and permanent teeth.

이온 주입이 금속의 일함수에 미치는 영향(Ⅱ)

백영환,김현경,강석태,황정남,이철주,최대선,정병두 연세대학교 자연과학연구소 1985 學術論文集 Vol.15 No.-

낮은 에너지 가속기를 제작하여 순도가 99.99%인 다결정 Ni에 Li^+ 이온을 7 keV의 에너지로 각 시료에 대한 이온주입율이 1.3×10^16atoms/㎠, 4.0×10^15atoms/㎠, 2.0×10^15atoms/㎠, 1.0×10^15atoms/㎠, 2.0×10^14atoms/㎠ 가 되도록 주입시킨 후 전자총과 억제 전위차형 에너지 분석기를 이용하여 일함수의 변화를 측정하였다. 이온 주입율이 2×10^15atoms/㎠보다 작을 때는 일함수가 1.9 eV까지 감소하였고 이온주입율이 4.0×10^15atoms/㎠보다 많을 때는 일함수가 2.8 eV까지 증가하였다. 이것은 Topping의 이론 및 Bauer의 실험결과와 일치함을 보였다. The changes in the work function of polycrystalline Ni with a purity of 99.99% due to Li^+ ions implanted using a low energy ion accelerator and retarding potential energy analyser(RPEA) have been studied. The implantation energy of the Li^+ ions is 7 keV and the implanted ion dose for the various samples are 1.3×10^16 atoms/㎠, 4.0×10^15 atoms/㎠, 2.0×10^15 atoms/㎠, 1.0×10^15 atoms/㎠ and 2.0×10^14 atoms/㎠. When the ion dose is less than 2×10^15 atoms/㎠ the, work function decreases to 1.9 eV, but when the ion dose is more than 4×10^15 atoms/㎠, the work function increses to 2.8 eV. These results are in good agreement with Topping's theory and Bauer's experiment.

정보보호경영시스템 규격분석에 관한 연구

황희두,추현민,김종훈 동아대학교 정보기술연구소 2006 情報技術硏究所論文誌 Vol.14 No.1

In the information society, security policy must be prepared in order to manage organization's information safely and by the security policy, security system must be developed and security management must be done. In order to do that, Understanding is required about International Organization for Standardization's Information Security Management System(ISO/BS17799:2002) and the organization that wants to certificate by using that understanding or the cooperation's security environment must magnify Security System's Correctness and Effectiveness. In this paper, We will analysis Information Security Management System's concept and then show you analysis about standard item of the cooperation that wants to certificate or the organization certification.

드부룬의 라텍스분리풍선카테타법에 의한 경동맥해면정맥동루 및 내경동맥 동맥류의 치료

장기현,한만청,김주완,한대희,최길수,심보성 대한신경외과학회 1984 Journal of Korean neurosurgical society Vol.13 No.1

The two cases, one carotid-cavernous fistula and one giant aneurysm of internal carotid artery, treated with Debrun's latex detachable balloon catheter technique are reported. Case 1 was a 50-year-old man who had proptosis, chemosis and 3rd nerve palsy in his right eye. His cerebral angiography showed typical traumatic carotid-cavernous fistula. Following complete radiologic and neurologic examination, the fistulous opening was successfully occluded with preservation of the internal carotid artery using latex detachable balloon. Immediately after occlusion of the fistula the clinical symptoms were markedly improved. Only transient facial pain occured as a complication. Case 2 was a 21-year-old woman who had a dizziness and left facial nerve palsy. The cerebral angiography showed a giant aneurysm at the petrous portion of left internal carotid artery. The patient tolerated occlusion of the left carotid artery. The left internal carotid artery was completely occluded with 3 detachable balloons. The patient had no complications during 9 days follow-up. The procedures and complications of detachable balloon catheter technique will be described and discussed.

글루콘산 생산을 위한 최적 배양조건

홍성란,이현절,정봉우,김춘영 全北大學校 1995 論文集 Vol.39 No.-

The production of gluconic acid by Aspergillus niger KCTC 2119 was studied. The Optimal culture conditions, such as initial pH, temperature, inoculum size and medium composition were established. Maximum overall gluconic acid productivity, 0.13g/L · hr was obtained when the cultivation was carried out at 33℃ and initial pH 5.5 for 72 hrs, with medium containing 110g/L glucose, 0.5g/L (NH_4)_2SO_4, 0.2g/L KH_2PO_4, 1.0g/L MgSO_4·7H_2O, and 0.1g/L corn steep liquor. The metabolic parameters such as specific growth rate, cell and gluconic acid yields were estimated for process improvement.

Chemical-Looping Combustion을 위한 금속산화물 매체들의 산화 환원 반응특성

이진배,송영욱,박주식,최상일,김영호,양현수 忠南大學校 産業技術硏究所 2003 산업기술연구논문집 Vol.18 No.2

Chemical-looping combustion has been focused as a very promising combustion technology from the viewpoint of high energy efficiency, easy separation of CO_(2) and no formation of NO_(x). The key of this combustion technology is to develop oxygen carrier mediums with high oxygen capacity, and high machanical and thermal stability. In this study, various kinds of mediums were prepared by the combination of active metal oxides, such as NiO, CoO, Fe_(2)O_(3) or NiO-Fe_(2)O_(3), with YSZ(yttria stabilized zirconia) as a binder. The redox reactions on the mediums were also carried out by using the thermogravimetric reactor. The redox reaction rates on a NiO/YSZ medium were found to be most superior in comparison with those of other mediums. In addition, durability of the medium was also found to be appropriate for UC. For the purpose of high redox reaction rates, the optimum reaction temperatures of reduction and oxidation on a NiO/YSZ medium were observed as 600℃ and l000℃, respectively.

Therapeutic Effect of Total Ginseng Saponin on Skin Wound Healing

Kim, Young-Soo,Cho, Ik-Hyun,Jeong, Moon-Jin,Jeong, Soon-Jeong,Nah, Seung-Yeol,Cho, Young-Sik,Kim, Seung-Hyun,Go, A-Ra,Kim, Se-Eun,Kang, Seong-Soo,Moon, Chang-Jong,Kim, Jong-Choon,Kim, Sung-Ho,Bae, Chu The Korean Society of Ginseng 2011 Journal of Ginseng Research Vol.35 No.3

In this study, we investigated the effects of total ginseng saponin (TGS) on the cutaneous wound healing process using histological analysis. A total of 24 ICR mice, 5-weeks-old, were used for all in vivo experiments. Mice were divided into control and TGS-treated groups and four equidistant 1-cm full-thickness dorsal incisional wounds were created. The wounds were extracted at days 1, 3, 5, and 7 post-injury for histomorphometrical analysis including wound area and contracture measurements, keratinocyte migration rate, and calculation of infiltrating inflammatory cells. The results showed that the wound area was smaller and keratinocyte migration rate was higher in the TGS-treated group than that of the control group from days 3 to 7. Inflammatory cells in the TGS-treated group at days 1 and 3 were reduced compared to the control group. Wound contraction in the TGS-treated group was greater than in the control group on days 3 to 5, and collagen deposition in the TGS-treated group was higher than in the control group during wound healing. The results indicate a beneficial effect of TGS when used to treat skin wounds.

Unenhanced Breast MRI With Diffusion-Weighted Imaging for Breast Cancer Detection: Effects of Training on Performance and Agreement of Subspecialty Radiologists

Kim Yeon Soo,Lee Su Hyun,Kim Soo-Yeon,Kim Eun Sil,Park Ah Reum,Chang Jung Min,Park Vivian Youngjean,Yoon Jung Hyun,Kang Bong Joo,Yun Bo La,Kim Tae Hee,Ko Eun Sook,Chu A Jung,Kim Jin You,Youn Inyoung,C 대한영상의학회 2024 Korean Journal of Radiology Vol.25 No.1

Objective: To investigate whether reader training improves the performance and agreement of radiologists in interpreting unenhanced breast magnetic resonance imaging (MRI) scans using diffusion-weighted imaging (DWI). Materials and Methods: A study of 96 breasts (35 cancers, 24 benign, and 37 negative) in 48 asymptomatic women was performed between June 2019 and October 2020. High-resolution DWI with b-values of 0, 800, and 1200 sec/mm2 was performed using a 3.0-T system. Sixteen breast radiologists independently reviewed the DWI, apparent diffusion coefficient maps, and T1-weighted MRI scans and recorded the Breast Imaging Reporting and Data System (BI-RADS) category for each breast. After a 2-h training session and a 5-month washout period, they re-evaluated the BI-RADS categories. A BI-RADS category of 4 (lesions with at least two suspicious criteria) or 5 (more than two suspicious criteria) was considered positive. The per-breast diagnostic performance of each reader was compared between the first and second reviews. Inter-reader agreement was evaluated using a multi-rater κ analysis and intraclass correlation coefficient (ICC). Results: Before training, the mean sensitivity, specificity, and accuracy of the 16 readers were 70.7% (95% confidence interval [CI]: 59.4–79.9), 90.8% (95% CI: 85.6–94.2), and 83.5% (95% CI: 78.6–87.4), respectively. After training, significant improvements in specificity (95.2%; 95% CI: 90.8–97.5; P = 0.001) and accuracy (85.9%; 95% CI: 80.9–89.8; P = 0.01) were observed, but no difference in sensitivity (69.8%; 95% CI: 58.1–79.4; P = 0.58) was observed. Regarding inter-diffusionreader agreement, the κ values were 0.57 (95% CI: 0.52–0.63) before training and 0.68 (95% CI: 0.62–0.74) after training, with a difference of 0.11 (95% CI: 0.02–0.18; P = 0.01). The ICC was 0.73 (95% CI: 0.69–0.74) before training and 0.79 (95% CI: 0.76–0.80) after training (P = 0.002). Conclusion: Brief reader training improved the performance and agreement of interpretations by breast radiologists using unenhanced MRI with DWI.