The Effects of Optic Disc Factors on Retinal Nerve Fiber Layer Thickness Measurement in Children

Jong‐,Hwa Jun,Se‐,Youp Lee 대한안과학회 2008 Korean Journal of Ophthalmology Vol.22 No.2

Purpose: We analyzed the effect of the changes of the optic disc area (ODA) caused by the axial length and the refractive error, and the consequent changes of the distance from the optic disc margin to the circular scan (OD‐CS) of Optical coherence tomography (OCT) on the measurement of the retinal nerve fiber layer thickness(RNFLT) were examined. Methods: One hundred two eyes of 51 children (age range 4 to 15 years) were measured using OCT including the RNFLT. For the ODA and the OD‐CS, the relative area formed by the ODA and the circular scan was obtained. In addition, the correlation of the refractive error and the axial length to the optic disc factors was assessed. Results: As hyperopia progresses to myopia, the axial length became longer, the ODA became smaller (r=‐ 0.442, p=0.000) and the OD‐CS showed a tendency to increase (r=0.471, p=0.000). As the OD‐CS became longer, the measured average RNFLT decreased significantly (r=‐0.248, p=0.012), and the ODA and the ODCS showed a significant correlation to the RNFL thickness that was measured in the nasal and inferior areas, the S2, N2 and N3 areas and the I1 area. Conclusions: As ODA becomes smaller and the OD‐CS becomes longer, the RNFLT measured in the nasal and inferior areas, the S2, N2, N3, I1 area has a tendency to be thinner. Hence, consideration of the disc area is required when interpreting the RNFLT of these eyes. Korean Journal of Ophthalmology 22(2):115-122, 2008

록인 증폭기에 의한 L(C,R) 회로 공진점 결정의 한 방법

정세민,홍진태,최규황,노지현 東亞大學校 附設 基礎科學硏究所 1994 基礎科學硏究論文集 Vol.11 No.1

L(C,R)회로의 공진점을 결정하기 위해 록인 증폭기에 의한 sequential spectrum analysis(SSA)법을 적용해 보았다. 시료는 변압기였으며, 단일 소인방식과 왕복 소인방식을 비교해 보았다. 또한 실험 결과의 신뢰도를 확인해보기 위해 실험결과를 변압기의 제작사 자료와 Q 미터(HP,4277A USA)에 의한 측정 결과와 비교하였다. 제작사 자료에 의하면 시료의 공진점은 두 권선의 각각은 5kHz(10kHz/2)였으나, 왕복소인에 의한 측정에서 시료의 공진점은 5.1kHz, 실험 결과로부터 계산된 Q 값은 4.3으로 주어졌고, 단일 소인법에 의해서는 공진점이 5.78KHz로 주어졌으며, Q 미터에 의한 Q 값은 4.9(9.8/2)였다. 실험 결과들과 기준 Q 미터에 의한 측정결과를 비교해본 결과, 양방향 소인법이 단일 방향소인법 보다 더 신뢰할 수 있음을 알 수 있었으며, SSA법에 의한 측정이 기존의 상용 전문기기에 의한 측정에 못지 않음과 전문기기의 측정 하한 문제를 극복하는 좋은 대안이 될 수 있음을 알 수 있었다. An accurate method named the sequential spectrum analysis(SSA) using a lock-in amplifier(LIA) of the heterodyne type was investigated to determine the resonance frequency of a LC(C,R) circuit : A heavy winding transformer was used as an inductor in the circuit. In this experiment, two types of the sweep method-one way and round trip method were examined. The resonance frequency of each method were compared with the manufacturer's data and those by the reference Q meter(HP,4277A, USA)for the experimental confidence: Measured resonance frequency by the round-trip method was 5.1 kHz, Q value at this frequency was about 4.3, while those by the single-sweep method were given by 5.78 kHz for the resonance frequency, 2.3 for the Q. On the other hand, the resonance frequency of manufacturer's data was 5 kHz and Q value by the reference Q meter was 4.9(9.8/2)at that frequency. From the comparison, it might be concluded that the SSA by the round-trip method was more reliable and accurate than the one-way method and relatively inexpensive, good alternative with respect to the professional instrument.

공동주택 바닥충격음 차단성능 평가

윤세철,오종민 慶熙大學校 地球環境硏究所 2002 지구환경논문집 Vol.13 No.-

In apartment buildings, floor-impact sound has been regarded as the major source which induces complaints from residents. It is mainly due to the use of light-weight structures and the lack of researches in terms of the sound transmission characteristics through the structures of a receiving room. The vibration produced by the impact on one part of an apartment building would travel as far as the other parts of structure only with with a little alleviation. As a result, the impact sound from upstairs has been regarded as a main source of noise causing discontentment among occupants. This study was carried out to measure the floor-impact sound levels and evaluate the insulation performance of floor-impact sound for the K apartment buildings which complaints induced and the newly-founded Y apartment buildings. The major results of this study are as followers; 1. The comparison showed that the light-impact sound levels and the levels of estimated light-impact sound ranged from 51.0dB to 73.9dB and 60dB to 66dB in the K apartment buildings, 50.2dB to 70.6dB and 57dB to 62dB in the Y apartment buildings. 2. The levels of estimated impact sound exceed the criteria of light-impact noise insulation 58dB by 6∼8dB and the criteria of heavy-impact noise insulation 50dB by 4∼6dB in the K apartment buildings and 4dB, 1dB in the Y apartment buildings, respectively.

Let 구문의 화행

최세종 현대영미어문학회 2000 현대영미어문학 Vol.17 No.2

This paper is concerned with the analysis of illocutionary forces from for-constructions in terms of speech act theory: constructions containing for which seem to have the force of imperatives. Chapter Ⅱ examines the mood and the functions of the constructions with let at the beginning of sentence followed by first or third person subject in the objective case. Chapter Ⅲ investigates the previous studies of the feta-constructions and the semantic analyses of them. In terms of its syntax, there are three distinct forms of for-constructions: imperatives with feta as their main verb, the constructions with for, and the constructions with let's. The let as main verb means allow to in prepositional content P but the meanings of the second let and third let in let's above is not realized in prepositional content P. Because of the property, let or let's is called a marker. Chapter Ⅳ sets out the felicity conditions of directive illocutionary acts, and the possibility of applying those conditions to illocutionary acts of for-constructions. Chapter Ⅴ analyzes the illocutionary acts of feta-constructions extracted from 12 movie scenarios by using the felicity conditions set up in Chapter Ⅲ. 95% of 58 English native speaker questionnaires support the pragmatic meanings which I analyzed in this study. The result of the analysis shows that almost all the respondents of English native speakers in each illocutionary act well recognize the directive meanings of feta-constructions by answering the propel illocutionary acts in context. In conclusion, one proper illocutionary force corresponding to each situation is recognized by the background knowledge although the for-constructions have various illocutionary forces by the notional subjects. Therefore, this study shows that the pragmatic factors in conversational situations as well as the linguistic forms of for-constructions are important to comprehend the speaker's utterance meanings in the discourse context.

골격성 3급 부정교합자시 악교정 수술후 골격이동량에 따른 설골의 위치와 상기도 변화에 관한 연구

조세종,김여갑 대한악안면성형재건외과학회 2000 Maxillofacial Plastic Reconstructive Surgery Vol.22 No.3

The goal of this study is the comparison of upper airway size and change of skeletal Class I group and skeletal Class III group (before operation, within 2 weeks after operation, 6 months after operation) respectively. At first, we measured the lines between selected upper air way landmarks on lateral cephalometric x-ray film of skeletal Class I 40 persons whoes age were 23-26 years old, ,and did the same lines of landmarks of skeletal Class III 44 persons who had not been operated yet, were within 2 weeks after operation, were 6 months after operation. And we compared it respectively and analyzed it with paired t-test. We studied the relationship of those on produced data. 1.Skeletal Class III group was narrower in nasopharyngeal air way space than that of skeletal Class I group, and increased in thickness of oropharyngeal, hypopharyngeal wall within 2 weeks after operation, and reduced in nasopharyngeal, oropharyngeal air way space, and did in thickness of nasopharngeal, hypopharyngeal wall 6 months after operation. 2.Skeletal Class III group reduced in nasopharyngeal, oropharyngeal air way space, and increased in thickness of nasopharyngeal, oropharyngeal, hypopharyngeal wall within 2 weeks after operation, restored the thickness of nasopharyngeal, oropharyngeal wall, but did not restored nasopharyngeal, oropharyngeal, hypopharyngeal air way space. 3.Vertical length from hyoid bone to mandibular plane did not have signifacant difference from Class I group but after operation, it increased more than Class I group significantly. 4.The size of airway reduced after operation. Among this, oropharyngeal airway most reduced.

Bi계 고온 초전도체의 Flux Pinning Cener의 연구

이세종 慶星大學校 1998 論文集 Vol.19 No.1

It has been investigated the effect of excess amount of Ca and Cu on the formation of Bi-2223 superconducting phases. MgO particles are also added as flux pinning sites in the Bi based material and observe their effect on the superconducting properties. Heat treatment are varied to see the influence of the experimental factors in terms of temperature and duration time. Results are analyzed by the X-ray diffraction, SEM and measurements of superconducting properties including critical current density.

비복신경이식을 이용한 긴 거리의 말초신경 결손부 수복

이종호,이세영,김명진,이은진,안강민,김성민,최원재,명훈,황순정,서병무,최진영,정필훈 大韓顎顔面成形再建外科學會 2003 Maxillofacial Plastic Reconstructive Surgery Vol.25 No.2

The surgery of oral and maxillofacial area poses the risk of cranial nerve damage such as trigeminal nerve or facial nerve. Inferior alveolar nerve is prone to damage in the third molar extraction, implant installation, orthognathic surgery, open reduction and rigid fixation, and tumor ablation surgery. On the other hands,facial nerve is likely to be damaged or sacrificed with trauma or parotidectomy. In case of inferior alveolar nerve injury, the incidence is reported to be about 1.3%. The nerve function will almost recover in minimal damage, but it won't recover at last in total damage of a part of nerve unit. In latter cases, nerve regeneration in intended by allograft as nerve substitute or various route of merve condit. But the recovery with autograft is believed to be most relialbe mrthod in the rapair of long-span(longer than 15㎜)nerve defect. We have performed autologous sural nerve graft in the repair of nerve defect, which is caused by resection of benign or malignant tumor. Hereby we report the method of nerve harvesting, recovery of defected peripheral nerve and the complications of donor site with the discussion of sural nerve anatomy.

분산 객체 기반 실시간 오디오/비디오 스트림 서비스의 설계 및 구현

김종현,박세철 동의공업대학 1999 論文集 Vol.25 No.1

This paper present a design and implementation of a realtime audio/video stream service based on distributed objects. Our design abstracts software components concerning the processing of audio/video as distributed objects. And we separates the transmission path of control data and media data for efficient stream transfer. Our total system architecture composed of three component systems, called Storgae Server, Control Server and Client. So we can extend systems easily in distributed environments. As proof concept, we implement a prototype system using distributed objects which support realtime audio/video stream services.

Interleukin-2가 Mouse 폐장의 폐포간 중격의 미세구조에 미치는 영향

황세진,김종우,정호삼,이규식 한양대학교 의과대학 1990 한양의대 학술지 Vol.10 No.1

Interleukin-2, a kind of lymphokine which is produced by activated T-lymphocytes during an immune response, is known to act not only as a growth factor for many cells of immune system but stimulates differentiation of cells of immune system. Although interleukin-2 is a useful agent for cancer immunotherapy and inhibiting agent of tumor cell metastasis, administration of interleukin-2 to cancer patient may cause various side effects such as pulmonary edema due to capillary leakage. In this experiment the author pursued the effects of interleukin-2 on ultrastructure of interalveolar septum in lung of mouse. Healthy male mice weighing about 20gm were used as experimental animals and divided into control group and experimental group. During the experiment water and foods were given ad libitum. Animals of control group were injected 0.2 ml of distilled water and animals of experimental grouup were injected 2 million units per kg body weight of interleukin-2 intraperitoneally Experimental animals were sacrified at 3 hours, 6 hours, 12 hours, 24 hours, 48 hours and 72 hours after administration and lung specimens were obtained. All specimens, which were prefixed in 2% glutaradehyde-2.5% paraformaldehyde and postfixed in osmium tetraoxide were dehydrated and embedded in Epon Araldite 502. Ultrathinsection about 600-800 in thickness, and uranyl acetate and lead citrate double stain were performed and all electron microscopic specimens were observed with JEM 100cx-II electron microscope. The results obtained were as follows: 1. The type I pneumocyte of interalveolar septum of lungs in interleukin-2 treated mice were swollen, separated from basal lamina. 2. Capillary endothelial cell of interalveolar septum of lungs in interleukin-2 treated mice were swollen, and pinocytic vesicles in endothelial cell were enlarged and increased in number. 3. Lamellar bodies of type II pneumocytes of interalveolar septum of lungs in interleukin-2 treated mice were enlarged, and vacuolized. 4. Mitochondria and microvilli of type II pneumocytes of interalveolar septum of lungs in interleukin-2 treated mice were decreased in number. It is consequently suggested that interleukin-2 induces intracellular edema of both the type I pneumocyte and the endothelial cell and damages to type II pneumocyte of interalveolar septum of lung in mice but alveolar epithelial cells and endothelial cells are recover as time goes by.

황화수소 중독증 2례

김종구,이경종,이세휘,박재범 大韓産業醫學會 2000 대한직업환경의학회지 Vol.12 No.1

평택시에 위치한 펄프 회사에서 탱크 내부를 청소하고자 근로자가 탱크 속으로 들어가는 도중 의식을 잃었다. 펄프제지 과정에서 유기물질의 발효로 인하여 유해한 가스가 발생한다. 발생할 수 있는 가스의 종류에는 이산화탄소(CO₂), 일산화탄소(CO), 암모니아(NH₃), 황화수소(H₂S) 그리고 메틸 머캅탄(methyl mercaptans, CH₃SH) 등이 있다. 작업환경 측정전 이러한 가스들이 존재할 것으로 추정하였으나 실제적으로 황화수소와 일산화탄소만 검출되었을 뿐 암모니아와 메틸 머캅탄은 측정되지 않았다. 그런데 상기 환자들에 있어서 HbCO이 정상 범주이므로 일산화탄소의 중독은 배제할 수 있었다. 따라서 황화수소 중독에 의한 의식소실임을 알 수 있었다. Hydrogen sulfide poisoning is frequently encountered in the workplace. Two workers lost their consciousness In an underground tank at a factory producing paper. The tank contained liquid mixture of used paper, sodium oxygenate chloride (NaOCl), and sodium thiosulfate pentahydrate(Na₂S₂O₃.□H₂O). A worker(worker A; 36-year-old man) entered tank to remove sludge. When worker A lost his consciousness, worker B entered the tank to rescue worker A, however he lost consciousness inside the tank. We discuss in detail the clinical features of this condition. Hydrogen sulfide poisonings have occurred in industries involving petroleum refining, the manufacture of heavy water, tanning of hides, vulcanization of rubber, and the manufacture of rayon. And it is necessary to stress the health education for workers and managers in these industries.