• 한국구조물진단유지관리공학회 논문집
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• 제4권4호
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• pp.211-218
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• 2000

Many bridges are severely damaged by the overloaded heavy vehicle and the trend will become more serious because the traffic volume is continuously increasing. Currently, the vehicles with gross weights over 40 tonf or axle weight over 10 tonf are not allowed on the public road. However, this regulation is not based on a systematic study on the bridge capacity and assumed to be much too conservative depending on the vehicle types and bridge types. In this study, the permit weights of heavy vehicles of diverse axle spacings and axle load distribution are calculated considering the structural characteristics of bridge superstructures. In order to consider the various load effects of heavy weight vehicle crossings, three conditions are considered in the calculation of permit vehicle load. From the results, the permit vehicle weights of the simple girder bridges are calculated.

• 한국윤활학회:학술대회논문집
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• 한국윤활학회 2001년도 제33회 춘계학술대회 개최
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• pp.89-95
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• 2001

The fretting wear characteristics of Zircaloy-4 tube at room and high temperature were Investigated experimentally. In this study, the number of cycles, slip amplitude and temperature were selected as main factors of fretting wear. The results of this research showed that the wear volume Increased with the Increase of slip amplitudes and the number of cycles but decreased with temperature and the coefficient of friction were observed different tendency between room and high temperature. According to SEM(EDS) only gross slip were observed on the surface of both specimens and compacted oxide were on worn surfaces. XRO patterns showed that the crystallization of ZrO$_2$ were observed on the worn surface at high temperature. The fretting wear were Investigated due to oxidation and accumulation of plastic flow.

• Radiation Oncology Journal
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• 제29권4호
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• pp.219-227
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• 2011

Purpose: This study evaluated the treatment effectiveness and proper radiation dose of helical tomotherapy (HT) in spine oligometastases from gastrointestinal cancers. Materials and Methods: From 2006 to 2010, 20 gastrointestinal cancer patients were treated with HT for spine oligometastases (31 spine lesions). The gross tumor volume (GTV) was the tumor evident from magnetic resonance imaging images fused with simulation computed tomography images. Clinical target volume (CTV) encompassed involved vertebral bodies or dorsal elements. We assumed that the planning target volume was equal to the CTV. We assessed local control rate after HT for 31 spine metastases. Pain response was scored by using a numeric pain intensity scale (NPIS, from 0 to 10). Results: Spine metastatic lesions were treated with median dose of 40 Gy (range, 24 to 51 Gy) and median 5 Gy per fraction (range, 2.5 to 8 Gy) to GTV with median 8 fractions (range, 3 to 20 fraction). Median biologically equivalent dose (BED, ${\alpha}/{\beta}$ = 10 Gy) was 52 $Gy_{10}$ (range, 37.5 to 76.8 $Gy_{10}$) to GTV. Six month local control rate for spine metastasis was 90.3%. Overall infield failure rate was 15% and outfield failure rate was 75%. Most patients showed pain relief after HT (93.8%). Median local recurrence free survival was 3 months. BED over 57 $Gy_{10}$ and oligometastases were identified as prognostic factors associated with improved local progression free survival (p = 0.012, P = 0.041). Conclusion: HT was capable of delivering higher BED to metastatic lesions in close proximity of the spinal cord. Spine metastases from gastrointestinal tumors were sensitive to high dose radiation, and BED (${\alpha}/{\beta}$ = 10 Gy) higher than 57 $Gy_{10}$ could improve local control.

• Journal of Korean Neurosurgical Society
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• 제42권4호
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• pp.276-280
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• 2007

Objective : The purpose of this study was to review the characteristics of falcine meningioma retrospectively and to identify the parameters associated with tumor recurrence. Methods : The analysis included; age, sex, extent of resection, and radiologic and pathologic findings. Falcine meningiomas were classified by location as anterior, middle, or posterior as described for parasagittal meningiomas. Results : Of the 795 meningioma patients treated between 1990 and 2004 at the authors' institution, 68 patients with meningiomas arising from the falx underwent craniotomies. There were 22 male and 46 female patients (1:2.1). Mean age was 55 years and ranged from 14 to 77 years. Locations of falcine meningioma were; the anterior third in 33 cases, middle in 20, and posterior in 15. Mean tumor volume was 42 cc and ranged from 4 to 140 cc. In 58 of the 68 patients tumors were totally removed. Additional surgery for recurrence was performed in 6 patients over 15 years. Of these 6 patients, only two patients underwent gross total tumor resection at first operation; the other four underwent subtotal tumor resection. Based on pathologic reports, the largest tumor subtype was transitional. There were four patients with a high grade tumor-three atypical and one anaplastic meningioma. Of the 68 patients, 59 achieved a good outcome (no neurological deficit or recurrence), six had temporary complications, two suffered new permanent postoperative deficits, and the remaining one died due to severe brain swelling despite postoperative intensive care. Extent of surgical resection was found to be significantly related to tumor recurrence. Conclusion : Falcine meningioma accounted for 8.5% of intracranial meningiomas and the transitional meningioma was the most common subtype of falcine meningioma. Gross total resection of tumor was the single most important predictor of an improved surgical outcome.

• Biomolecules & Therapeutics
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• 제18권1호
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• pp.111-121
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• 2010

In order to investigate the preliminary repeat oral dose toxicity and to determine the highest dosage for further 4-week repeated dose toxicity test, Low Molecular Weight Fucoidan (LMF) has been showed various pharmacological effects, was orally administered to female and male rats, once a day for 14 days at dose levels of 2,000, 1,000, 500 and 0 (vehicle control) mg/kg (body weights) in a volume of 10 ml/kg. The mortality and changes on the body weights, clinical signs, hematology, serum biochemistry and gross observations were monitored with organ weight and histopathology of principle organs. As the results of 14-day repeated oral treatment of LMF, no LMF treatment related mortalities were detected up to 2,000 mg/kg in both male and female rats, respectively. In addition, no noticeable changes on the body weight and clinical signs were detected except for significant decreases on the body weights and gains restricted to male 2,000 mg/kg treated groups as compared with male vehicle control. No meaningful changes on the organ weights, hematological, serum biochemistrical, gross and histopathological findings were observed. Therefore the highest dosage in the 4-week repeated dose toxicity test is suggested as 2,000 mg/kg in both female and male rats, respectively.

• 한국수소및신에너지학회논문집
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• 제24권6호
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• pp.524-534
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• 2013

Gasoline direct injection(GDI) engine has a high thermal efficiency, but it has a problem to increase carbon emissions such as soot and $CO_x$. In this study, the objective is to analyze numerically a problem for adding the hydrogen during the intake stroke so as to reduce the injected amount of gasoline in GDI engines. For selection of the base model, the cylinder pressure of simulation is matched to experimental data. The numerical analysis are carried out by a CFD model with the hydrogen addition of 2%, 3% and 4% on the volume basis. In the case of 3% hydrogen addition, the injected gasoline amount is only changed to match the maximum pressure of simulation to that of the base model for additional study. It is found that the combustion temperature and pressure increase with the hydrogen addition. And NO emission also increases because of the higher combustion temperature. $CO_x$ emissions, however, are reduced due to the decrease of injected gasoline amount. Also, as the injected gasoline amount is reduced for the same hydrogen addition ratio, the gross indicated work is no significant, But NO and $CO_x$ emissions are considerably decreased. On the order hand, $CO_x$ emissions of two cases are more decreased and their gross indicated works are higher obtained than those of the base model.

• 한국의류학회지
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• 제31권1호
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• pp.33-43
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• 2007

Middle age is the time of the most important meaning in life and also the time of physical and mental change, which offers new social activities for self-development. Middle-aged women form the major consumer class in current clothing industry, but few have been performed on this so far. The researcher studied in many aspect on the clothes which middle-aged women need to wear during this period of change. Thus this study is executed to examine what benefits middle-aged women pursue in clothing attitudes and the relationship among clothing pursuit benefit and their somatotype compensation and image orientation. The research performed the theoretical study and practical study simultaneously. The subjects are 238 middle-aged women between 35 and 49 years old in September, 2004. The results of this study are as follows: 1. The attitude of women's clothing patterns in relation with image consist of two factor structures. One is the body image and the other is the appearance image. 2. As a result of researching the attitude for choosing clothes of each body group by Rohrer index, the women with gross body group take a top priority for the lower-body compensation, while the women with slim body group take a top priority for volume compensation. 3. As a result of researching the cognitive somatotype group's attitude for choosing clothes, gross body group takes a top priority for lower-body compensation and upper-body compensation. 4. As a result of researching the relationship between real somatotype and cognitive somatotype by Rohrer index, middle-aged women think of themselves as being fatter than present state. And choosing the clothes, the body misunderstanding group of women usually show that they consider more compensation than the normally body understanding group. 5. The evaluation on real somatotype, cognitive somatotype, ideal somatotype influences on the body cathexis.

• 대한방사선치료학회지
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• 제35권
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• pp.41-51
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• 2023

목 적: 본 연구는 폐암 환자의 정위체부방사선치료 시(Stereotactic Body Radiation Therapy, SBRT) 기준선(Baseline) 변화에 따른 3D-CBCT(Cone Beam Computed-Tomography)와 Gated-CBCT의 영상 품질(Image quality)을 비교 분석하여 호흡에 따른 움직임의 보정에 유용한 CBCT 촬영 방법을 찾고자 한다. 대상 및 방법: QUASAR^TM(Modus Medical Devices Inc, Canada) 팬텀에 지름이 3 cm인 고체 종양 물질(Solid Tumor)을 삽입하여 팬텀의 속도를 주기 3 sec, 최대 진폭 20 mm 로 4DCT(4-Dimentional Computed-Tomography)를 촬영하였다. 전산화 치료계획시스템 Eclipse^TM을 이용하여 고체 종양 물질에 육안적 종양용적(Gross Target Volume, GTV)을 윤곽 묘사하였다. Truebeam STx^TM을 이용해 4DCT 촬영 시와 동일하게 설정한 후, 기준선 변화가 1 mm, 3 mm, 5 mm인 호흡 패턴을 팬텀에 입력하여 3D-CBCT(Spotlight, Full)와 Gated-CBCT(Spotlight, Full) 영상을 5회 반복하여 획득하였다. 획득된 영상을 4DCT 영상을 기준으로 신호대잡음비(Signal-to-Noise Ratio, SNR), 대조대잡음비(Contrast-to-Noise Ratio, CNR), 종양 체적 길이(Tumor Volume Length) 및 모션 블러링 비(Motion Blurring Ratio, MBR)를 측정하여 비교하였다. 결 과: Spotlight Gated-CBCT 영상이 기준선 변화에 따른 신호대잡음비가 평균 13.30±0.10%, 대조대잡음비가 평균 7.78±0.16%, 종양 체적 길이가 평균 3.55 ± 0.17%, 모션 블러링 비가 평균 1.18 ± 0.06%로 Spotlight 3D-CBCT보다 우수한 값을 보였다. 또한, Full Gated-CBCT 영상이 기준선 변화에 따른 신호대잡음비가 평균 12.80 ± 0.11%, 대조대잡음비가 평균 7.60 ± 0.11%, 종양 체적 길이가 평균 3.54 ± 0.16%, 모션 블러링 비가 평균 1.18 ± 0.05%로 Full 3D-CBCT보다 우수한 값을 보였다. 결 론: 3D-CBCT 촬영 영상과 비교하여 Gated-CBCT 촬영 영상이 기준선 변화에 따른 영상 품질이 우수한 값을 보였으며, 호흡으로 인한 모션 블러링 인공물(Motion Blurring Artifacts)의 영향이 적은 것을 확인했다. 따라서 단기간에 고선량을 전달하는 폐암의 정위체부방사선치료 시 불규칙한 호흡으로 인한 기준선 변화가 발생하는 경우 Gated-CBCT를 이용해 영상유도(Image Guide)를 하는 것이 유용하다고 판단된다.

• Radiation Oncology Journal
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• 제15권4호
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• pp.387-392
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• 1997

목적 : ICRU 50의 권고에 따라 치료 범위를 Planning Target Volume(PTV)으로 설정하고 있다. 진단 영상장치의 발달과 특히 CT Simulator 등의 도움으로 Gross Tumor Volume(GTV) 설정은 쉬워지고 있으나, 내부장기의 움직임에 의한 경계의 선정에 대하여는 특별한 지침이 없고, 단지 경험에 의존하고 있는 실정이다. 본 연구에서는 폐의 움직임 유형을 분석하여 폐 부위의 PTV설정시 폐의 움지임을 고려쓿기 위한 정량적인 지침을 마련하려는데 있다. 대상 및 방법 : 폐암, 식도암 등 폐 및 흥부 주변의 방사선으로 치료받는 환자 10명을 대상으로 Simulator 투시 촬영기로 폐의 움직임을 관찰하였다. 우측 폐는 12부위와, 좌측 폐는 10부위로 각각 나누었다 우측 폐 부위는 상엽은 2부분, 중엽은 2부분, 하엽은 2부분으로.나누었고, 그 각각을 측면에서 전, 후 2부분으로 나누었다. 좌측 폐 부위는 상엽, 하엽 모두 2부분으로 나누고, 측면에서 다시 전, 후로 다시 2부분으로 나누었다. 부위마다 4-5점을 택해 X선 투시 장치에서 생성된 열상을 컴퓨터에 입력시켜 폐포의 움직임을 x, y, z 3좌표 방향으로 수치화 하였다. 결과 :우측과 좌측 폐 부위 중 안측 상엽 부위의 움직임이 상대적으로 적었으며, 좌우 이동이 전후 이동에 비해 크게 나타났다. 좌우 이동은 심장 박동 효과로 심장 또는 대동맥 근처에서 가장 두드러지게 나타나서 양측 패문 부위가 가장 큰 이동을 보였으며(평균 6.6mm), 상하 이동은 호흡 효과로 양측 폐 하엽 부위, 횡격막 근처에서 가장 컸다(평균 14.1mm). 결론 : X선 투시로 폐의 움직임을 관찰할 수 있으며 컴퓨터의 궤적 추적으로 정량화 할 수 있었다. 폐 부위의 방사선 치료시 설정되는 PTV에는 장기의 움직임을 고려해야 하는데 본 연구의 결과를 이용하여 치료 부위에 따라 여유를 차등을 둔다면 치료 조사면을 최적화 하는데 도움이 될 것으로 생각된다.

• Journal of Chest Surgery
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• 제9권2호
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• pp.239-244
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• 1976

Alterations in the serum magnesium level were studied in twenty patients who had open-heart surgery during the period from August 1974 to May 1975. The patients were chosen at random. The operative procedures included repair for congenital heart diseases in fifteen patients and cardiac valve replacement for acquired valvular heart diseases in five patients. The age ranged from 8 to 46 years, with an average of 19 years. None of the patients had a history of gross neuromuscular abnormalities. Cardiopulmonary bypass was carried out using a roller pump and a disposable oxygenator. The prime solution consisted of 2 units of ACD banked blood and approximately an equal volume of non-blood additives in adults, while a relatively smaller volume was added in children. The average flow rate was 2,733 ml per minute. Blood samples for magnesium and arterial blood pH were obtained the day after admission 25 minutes after initiation of the bypass and on the morning the day after operation. Preoperative data were then compared with those obtained during the bypass and postoperatively by a paired test. During the bypass, the serum magnesium level decreased significantly from $1.425{\pm}0.029$ to $1.210{\pm}0.063mEq.$ liter (p<0.001). Also, there was a significant decrease in serum magnesium from $1.425{\pm}0.029$ preoperatively to $1.255{\pm}0.083mEq$. per liter (p<0.001). Also, there was a significant decrease in serum magnesium from $1.425{\pm}0.029$ preoperatively to $1.255{\pm}0.083mEq$. per liter postoperatively (p<0.01). The duration of bypass was less than 90 minutes in 10 patients (group A) and exceeded 90 minutes in the remaining 10 (group B). There was no statistical correlation between the groups A and B ($p{\gg}0.20$). Statistical analyses of the serum magnesium level and arterial blood pH showed no significant correlation with correlation coefficient; being -0.3485(pre-op), -0.2971(during bypass), and -0.1008(post-op), respectively. In all the patients, no gross neuromuscular abnormalities were found postoperatively. At present, the clinical significance of the serum magnesium level during and after bypass is controversial. In the near future, however, it is expected that improvements in prime solution and heart-lung machine will solve this problem.