수종 한국산 식물성분의 항종양시험에 관한 연구

정원근 대한약학회 1973 약학회지 Vol.17 No.4

Four main components of plants produced in Korea were subjected to the screening test of antineoplastic activity against Ehrlich ascites carcinoma, SN 36 leukemia and sarcoma 180. Of the four components, bilobol showed comparatively active survival effect.

살구나무를 심는다

정원근 천년의시작 2004 (계간)시작 Vol.3 No.3

산에서 저수지를 만나다

정원근 천년의시작 2004 (계간)시작 Vol.3 No.3

양액 자동 공급 제어 시스템의 설계 및 구현

정원근,이병로,김병철,Jeong Won-Geun,Lee Byeong-Ro,Kim Byungcheul 한국정보통신학회 2005 한국정보통신학회논문지 Vol.9 No.5

본 연구에서는 임베디드 RTOS와 퍼지제어 알고리즘을 이용하여 양액의 농도와 공급량을 자동으로 조절하는 양액 공급 제어 시스템을 설계 및 구현하였다. 작물의 생육에 영향을 미치는 인자는 일사량, 외부온도, 외부습도, 생육단계로 구성하였으며, 양액온도, 전기전도도(EC), 산도(pH)가 측정되었다. 그 결과를 바탕으로 양액의 농도와 공급량 조절을 위해 양액 조절 퍼지제어 알고리즘을 개발하였다. 일반 사용자를 위하여 임베디드 RTOS, 한글 LCD, 그리고 그래픽으로 구성된 양액 전용 임베디드 제어기를 개발하였다. In this study, an nutrient solution control system have been designed and implemented, which controls the density of nutrient and the nutrient supply automatically using embedded real time operating system and fuzzy control algorithm. The factors which affect the growth of crop consist of solar radiation, external temperature, and external humidity. Also, nutrient temperature, electric conductivity(ED, and pH are monitored. According to the surveyed results, a fuzzy control algorithm for nutrient control is developed in order to control the density of nutrient and the nutrient supply. The exclusive embedded controller which consists of an embedded real time operating system, a korean LCD, and a graphic is developed for common users.

젓가락에도 상처가 핀다

정원근 천년의시작 2004 (계간)시작 Vol.3 No.3

s-Triazine의 환전환반응 - 1,3,5-Benzotriazepine의 합성 및 생리적 동배체성 평가 -

정원근,정낙신,신계정,정진현,김득준,천문우 대한약학회 1985 약학회지 Vol.29 No.2

A novel synthesis of 7-membered 1,3,5-benzotriazepine (IV) from 1,3-Dimethyl-5-azauracil in one step by s-Triazine ring transformation is reported.

Value of imaging study in predicting pelvic lymph node metastases of uterine cervical cancer

정원근,박경란,이경자,김규보,이지혜,정송미,김이준,김지영,윤혜전,강병철,구혜수,성순희,조민선,박상희 대한방사선종양학회 2017 Radiation Oncology Journal Vol.35 No.4

Purpose: To evaluate the diagnostic accuracy of computed tomography (CT), magnetic resonance imaging (MRI), and positron emission tomography/computed tomography (PET/CT) in predicting pelvic lymph node (LN) metastases in patients with cervical cancer. Materials and Methods: From January 2009 to March 2015, 114 patients with FIGO stage IA1-IIB uterine cervical cancer who underwent hysterectomy with pelvic lymphadenectomy and took CT, MRI, and PET/CT before surgery were enrolled in this study. The criteria for LN metastases were a LN diameter ≥1.0 cm and/or the presence of central necrosis on CT, a LN diameter ≥1.0 cm on MRI, and a focally increased FDG uptake on PET/CT. The sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy for pelvic LN metastases were estimated. Results: The sensitivity, specificity, PPV, NPV, and accuracy for detection of pelvic LN metastases were 51.4%, 85.9%, 41.3%, 90.1%, and 80.3% for CT; 24.3%, 96.3%, 56.3%, 86.8%, and 84.6% for MRI; and 48.6%, 89.5%, 47.4%, 90.0%, and 82.9% for PET/ CT, respectively. The sensitivity of PET/CT and CT was higher than that of MRI (p=0.004 and p= 0.013, respectively). The specificity of MRI was higher than those of PET/CT and CT (p=0.002 and p=0.001, respectively). The difference of specificity between PET/CT and CT was not statistically significant (p=0.167). Conclusion: These results indicate that preoperative CT, MRI, and PET/CT showed low to moderate sensitivity and PPV, and moderate to high specificity, NPV, and accuracy. More efforts are necessary to improve sensitivity of imaging modalities in order to predict pelvic LN metastases.

Displacement of Surgical Clips in Patients with Human Acellular Dermal Matrix in the Excision Cavity during Whole Breast Irradiation Following Breast-Conserving Surgery

정원근,김규보,백남선 대한암학회 2020 Cancer Research and Treatment Vol.52 No.2

Purpose The purpose of this study was to investigate the displacement of surgical clips in the excision cavity during whole breast irradiation following breast-conserving surgery (BCS) with or without acellular dermal matrix (ADM) insertion, and to analyze clinicopathologic factors associated with the displacement of surgical clips. Materials and Methods From 2016 to 2017, 100 consecutive breast cancer patients who underwent BCS with the placement of surgical clips (superior, inferior, medial, lateral, and deep sides) in the tumor bed were included in this study. All patients took first planning computed tomography (CT) scan (CT 1) before whole breast irradiation and second CT scan (CT 2) before boost irradiation. Between two sets of planning CT, the displacement of surgical clips was calculated from the !X (lateral–medial), !Y (anterior–posterior), !Z (superior–inferior), and threedimensional (3D) directions. Patients were divided into two groups according to the breast volume replacement with ADM: group A with ADM and group B without ADM. Results The means and 1 standard deviations of 3D displacement for superior, inferior, medial, lateral and deep clips were 5.2±2.9, 5.2±3.2, 5.6±4.5, 5.6±4.3, and 4.9±4.9 mm in entire cohort (n=100); 5.6±2.6, 6.0±3.5, 6.7±5.8, 6.7±5.7, and 6.1±7.4 mm in group A (n=38); 4.9±3.1, 4.8±3.0, 5.0±3.5, 5.0±2.9, and 4.3±2.8 mm in group B (n=62), respectively. The 3D displacements of group A were longer than those of group B, but only significant difference was observed in lateral clip (p=0.047). Conclusion This study demonstrated displacement of surgical clips during whole breast irradiation in patients with ADM insertion. For patients who had breast volume replacement using ADM, adaptive boost planning should be considered.

Analysis of Air Circulation in Oyster Mushroom Farm

정원근,김태한,임학규 한국농업기계학회 2012 바이오시스템공학 Vol.37 No.2

Purpose: Oyster mushroom farm which could not meet optimum temperature range yields non-uniform sized, low quality products. Thus, this study, utilizing STAR CCM+, one of the computational fluid dynamics (CFD) programs, analyzed the impact of air circulation and temperature distribution. Methods: After we visited numerous mushroom farms, we measured the temperature at the discharge ports of heaters, fan capacity, and the locations of the air circulators in the farms. According to the data, most mushroom growers installed the heaters near the entrance and discharge ports of the heaters at the third growing bed on the same height as the heaters in the entrance. The temperature at the discharge port of heater was 26°C, and the fan capacity was 4,500 m3/hr. The air circulator was placed in the center of the mushroom farm 50cm above the ground, and its capacity of inlet port was 1,100 m3/hr and discharge port 1,600 m3/hr. The mushroom farm was insulated. Results: According to the analysis of the temperature distribution in the vertical plane of the entrance side, no air circulation causes the high temperature zone of 296~299K at the discharge port of the heater to take up 34% of area while the operation of air circulators causes it to occupy only 9%. This means that not using air circulators leads to a concentration of high temperature at the discharge port near the entrance. In addition, with the results of the analysis of the temperature distribution in the vertical planes of the center, no air circulation causes the temperature zone of 295~298K at the discharge port of the heater to take up 48% of area while the operation of air circulators causes it to occupy 80%. This shows that the high outlet port temperature disseminated to the center. Conclusions: After ninety minute operation of both heater and air circulator, the interior temperature became stabilized in the mushroom farm. Air circulation made the high temperature at the discharge port disseminate to the center and exit in the farm and equalize the temperature distribution.

Warm with high color rendering index white light from hybridization of Ca2BO3Cl:Eu2+ yellow phosphor and CdSe/ZnS nanocrystals

정원근,김성현,정현철,이장훈 한국공업화학회 2013 Journal of Industrial and Engineering Chemistry Vol.19 No.5

Yellow emitting Ca2BO3Cl:Eu2+ phosphor was prepared by solid state reaction at 900 8C. The particle was monoclinic crystal structure, and showed broad band emission at around 540–590 nm due to the 5d–4f transition. Single Ca2BO3Cl:Eu2+ phosphor converted white LED exhibited the CIE coordinates of (0.3441,0.2675) with low CRI of 67.4. Hybridization of Ca2BO3Cl:Eu2+ with 535 and 610 nm emitting CdSe/ZnS nanocrystals contributed to increasing white spectrum and generated the warm color temperature (4055 K) with high CRI (83.9) of white light. The acceptable color stability was also observed from (0.3687, 0.3051) at 20 mA to (0.3645, 0.3101) at 80 mA.