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A Study on Energy Requirement Variation According to Energy Efficiency Rating Evaluation and Design Variable of Standard Design of Rural Houses (농촌주택표준설계도 에너지효율등급평가 및 설계변수에 따른 에너지소요량 변화에 관한 연구)

  • Park, Mi-Lan;Ryoo, Yeon-Su;Choi, Jeong-Man;Seo, Hye-Won
    • Journal of the Korean Institute of Rural Architecture
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    • v.19 no.2
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    • pp.9-16
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    • 2017
  • The study analyzed the heat losses and the building energy efficiency grade by the energy simulation using the ENERGY# and ECO2 programs for the three types of Standard design of rural houses. It was calculated the energy efficiency rating by the ECO2 program for the rural housing standard design, and the energy demand and the energy consumption by each factor were compared and analyzed. And it analyzed energy consumption by element of each house by ENERGY # program. As a result, first in the evaluation of the energy efficiency grade of buildings by the ECO2 program, the rating for primary energy requirement for the housing newly built by the standard design of rural house is expected to range from 2 to 4 with 189.3 to $238.7kWh/m^2.a$. Second, the energy loss of each part of standard design of rural housing occurs in the order of ventilation 39%, window 33%, outer wall 14%, roof 9%, bottom 5%, and energy loss through ventilation and window occurs more than 70%. Third, the most beneficial effects on the energy efficiency grade is obtained the lowest grade of all three types by 2 when the lowering of the window and door heat transmission rate and the lowering of the light density, and the heat exchange ventilation device is not installed. Fourth, in the standard design of rural housing, the energy demand is occupied by heating > hot water > lighting order, and the order of the weight is changed in order of heating > lighting > ventilation > hot water. Fifth, building energy efficiency assessment system needs to establish policy for fixing rural housing energy as a practical device to ensure energy performance and quality.

Intracranial Metaplastic Meningioma : Clinical and Radio-logical Characteristics of 11 Cases

  • Kim, Taehoon;Kim, Jin Wook;Ji, So Young;Kang, Ho;Kim, Kyung-Min;Kim, Yong Hwy;Park, Chul-Kee;Choi, Seung Hong;Park, Sung-Hye
    • Journal of Korean Neurosurgical Society
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    • v.63 no.5
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    • pp.657-663
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    • 2020
  • Objective : Metaplastic meningioma is an extremely rare subtype of World Health Organization (WHO) grade I meningioma. It has distinctive histological subtypes according to its own mesenchymal components. Owing to its scarcity, clinical or radiological features of a metaplastic meningioma are poorly described. Methods : Between 2004 and 2018, we analyzed total 1814 cases surgically proven meningioma for 15 years. Among them, metaplastic meningioma was diagnosed in 11 cases. Magnetic resonance images were taken for all patients, and computed tomography scan was taken for 10 patients. Results : WHO grade I meningiomas were 1376 cases (75.9%), 354 cases (19.5%) in WHO grade II, and 84 cases (4.6%) in WHO grade III meningiomas. Metaplastic meningioma was 11 cases as 0.8% of WHO grade I meningioma and 0.6% of entire meningiomas for 15 years. Among the entire 11 metaplastic meningiomas, five tumors (45%) were diagnosed as a lipomatous subtype with rich fat components, four (36%) as an osseous subtype with extensive bone formation and two (18%) as a xanthomatous subtype. There was no cartilaginous subtype metaplastic meningioma in our study. Lipomatous and osseous metaplastic meningioma have peculiar radiological characteristics according to mesenchymal components. Conclusion : We investigated a rare metaplastic meningioma subtype based on our 15-year surgical experience with meningiomas. Further investigation will be necessary for the clear clarification of tumor nature of this rare tumor.

Feasibility of Ultrasonic Log Sorting in Manufacturing Structural Lamination from Japanese Cedar Logs

  • Oh, Jung-Kwon;Yeo, Hwan-Myeong;Choi, In-Gyu;Lee, Jun-Jae
    • Journal of the Korean Wood Science and Technology
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    • v.39 no.2
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    • pp.163-171
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    • 2011
  • Because Japanese cedar shows lower mechanical performance, glued-laminated timber (glulam) can be a better way to utilize Japanese cedar for structural purpose. However, low yield of higher grade lamination from log makes it difficult to design structural glulam. This study was aimed to increase the yield of higher grade lamination and provide higher efficiency of manufacturing structural lamination by ultrasonic log sorting technology. Logs were sorted by an existing log grading rule regulated by Korea Forest Research Institute (KFRI). It was found that the KFRI log grading rule contributed to finding better logs in viewpoint of the volumetric yield and it can reduce the number of rejected lumber by visual grading. However, it could not identify better logs to produce higher-grade products. To find an appropriate log-sorting-method for structural products, log diameter and ultrasonic time of flight (TOF) for the log were considered as factors to affect mechanical performance of resulting products. However, it was found that influence of log diameter on mechanical performance of resulting products was very small. The TOF showed a possibility to sort logs by mechanical performance of resulting products even though a coefficient of correlation was not strong (R = 0.6). In a case study, the log selection based on the ultrasonic TOF of the log increased the yield of the outermost tension lamination (E8 or better grade, KS F 3021) from 2.6% to 12.5% and reduced LTE5 (lower than E5 grade) lamination from 43.6% to 10.3%, compared with the existing KFRI log grading rule.

Chest Wall Giant Malignant Peripheral Nerve Sheath Tumor -One case report (흉벽에 발생한 거대 악성 말초신경초종-치험 1례-)

  • Park, Jin-Gyu;Kim, Min-Ho;Jo, Jung-Gu
    • Journal of Chest Surgery
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    • v.30 no.7
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    • pp.729-732
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    • 1997
  • A case of chest wall malignant peripheral nerve sheath tumor(MPNST) was reported in the U.S.A by Mark and coworkers6)(1991), but none in korea. MPNST accounts for approximately 10% of all soft tissue sarcoma, mostly in patients between 20 and 50 years of age. MPNST arises in association with a major nerve trunk, including the sciatic nerve, brachial plexus, and sacral plexus and the most common anatomical site is the proximal portion of the upper and lower extremity and trunk. Surgical treatment is local excision of mass in low grade sarcoma but unblock resection is necessary in high grade sarcoma. We experienced multiple huge low grade MPNST on left chest wall of a 50 years old man. The tumor and invalved chest wall were removed, and the chest wall defect(15$\times$8 cm) was reconstructed with Teflon. Postoperative course was unevenful.

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Study of Drying Characteristics of Low Rank Coal in a Pressurized Micro-riser (가압 마이크로 수송관을 이용한 저급탄의 건조 특성 연구)

  • Gwak, In Seop;Gwak, You Ra;Kim, Ye Bin;Lee, See Hoon
    • Applied Chemistry for Engineering
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    • v.28 no.3
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    • pp.313-317
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    • 2017
  • With the continuous increase of energy demand, low-grade coal is regarded as one of new energy sources. However, due to the high water content, the utilization efficiency of low-grade coal is not good to be used in recent conversion plants. Therefore, it requires a drying process to lower the water content in low-grade coals. Although a variety of drying experiments were conducted, drying characteristics in accordance with the pressure change has not been progressed. In this study, the flash drying characteristics of low grade coal with high moisture content (21.5 wt%) were determined in a pressurized micro-riser. The effect of operation conditions such as pressure (1-40 bar), dryer temperature ($200-600^{\circ}C$), and tube length (2-6 m) on drying ratios were investigated.

A Study on the Improvement of Assessment Criteria for Housing Performance Indicator System and Green Building Certification Criteria (주택성능등급과 친환경건축물인증의 평가방법 비교를 통한 개선안 연구 -환경관련등급을 중심으로-)

  • Kim, Myoung-Shin;Hwang, Jae-Woo;Chun, Jung-Gil;Ha, Dae-Woong;Park, Kyung-Soon;Son, Won-Tug
    • Proceedings of the SAREK Conference
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    • 2009.06a
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    • pp.9-14
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    • 2009
  • A variety of Certification systems are initiated, as increased demands for housing quality of building & house owner. New building and apartment built in Seoul metropolitan should acquire Building Energy Rating System and Housing Performance Grade indication System, Green Building Certification System. Building Energy Rating System could be acquired through the certification from energy performance index of environment grade in Housing Performance Grade Indication. Between Housing Performance Grade Indication and Green Building Certification System, There are troublesome to acquire certification because a lot of assessment items are overlapped. At a result, the rational and efficient certification system should be initiated not only to avoid overlap among those certification systems and promote Green Building market share but also efficient certification system operation. We will discuss on assessment items between Housing Performance Grade Indication System and Green Building Certification System and release the improvement method those Certification Systems to avoid overlapping to assessment items.

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A Study on the Treatment of Suitable Flame Retardant to the Fibers for Welding Blanket Development (용접 불티 차단막 개발을 위한 섬유류의 적정 방염처리 방안 연구)

  • 이근원;김관응;이두형
    • Fire Science and Engineering
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    • v.16 no.3
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    • pp.48-55
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    • 2002
  • This study presents a treatment of suitable flame retardant through evaluating fire performance after treating flame retardant of fibers for development of welding blanket. The experimental samples used were commercial fibers and we are treated fibers with the flame retardant liquid and the flame retardant paint. The fire performance of the sample was carried out according to the Korea and Japan Standard. As the results of the fire performance experiment, the treated fiber in samples had enough in the performance of flame and fire retardant and the grade of their was from grade A to grade C according to flame and fire retardant standard. The lower oxygen index indicated that all treated samples with the resist are satisfied with international standard. We con-sider that the welding blanket treated with grade A, B and C performance prevents fire spread regardless of the height of work stairs in the case of installation horizontally. Also, it is considered that the welding blanket treated with grade C performance prevents fire spread regardless of the height of work stairs in the case of installation vertically.

The Elementary School Teachers' Conceptions and Utilization on the General Remarks in the Science Teacher's Guide (초등교사들의 과학 교사용 지도서 총론에 대한 인식과 활용 실태)

  • Jang, Myoung-Duk;Joung, Yong-Jae;Kim, Han-Je
    • Journal of Korean Elementary Science Education
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    • v.30 no.4
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    • pp.535-552
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    • 2011
  • The purpose of this study was to investigate elementary school teachers' conceptions on the general remarks (GR) in the new science teacher's guide, the teachers' conceptions on inservice training program of the GR, and their opinions of improvement on the GR. Also, the teachers' utilization of the GR was examined. The participants were 152 elementary school teachers who were teaching grade 3~6. A questionnaire was used to collect data. The results of this study are as follows; First, at least 13.2~17.1% of the teachers did not have specific conception of the purpose of the GR, and more than 90% of the teachers expressed that the GR is necessary in the teachers' guide. Second, about 60% of the teachers responded that the training program on the GR is necessary, and when the program is open, their most favorite agency and speaker were a provincial education office and a textbook developer(or author), respectively. Their most favorite time and period of the training program were the vacation and 15~30 hours, respectively. Third, the mean values on the frequency of use were lower than 3 point of the five-point Likert scale at both the GR for grade 3~4 and the GR for grade 5~6, and the teachers' main use of the GR was the planning a science lesson for an open class. Fourth, the teachers suggested various opinions and there was difference between the opinions about the GR for grade 3~4 and the opinions about the GR for grade 5~6.

A model to develop the porosity of concrete as important mechanical property

  • Alyousef, Rayed;Alabduljabbar, Hisham;Mohamed, Abdeliazim Mustafa;Alaskar, Abdulaziz;Jermsittiparsert, Kittisak;Ho, Lanh Si
    • Smart Structures and Systems
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    • v.26 no.2
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    • pp.147-156
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    • 2020
  • This numerical study demonstrates the porosity conditions and the intensity of the interactions with the aggressive agents. It is established that the density as well as the elastic modulus are correlated to ultrasonic velocity The following investigation assessed the effects of cement grade and porosity on tensile strength, flexural and compressive of Ultra High Performance Concrete (UHPC) as a numerical model in PLAXIS 2d Software. Initially, the existing strength-porosity equations were investigated. Furthermore, comparisons of the proposed equations with the existing models suggested the high accuracy of the proposed equations in predicting, cement grade concrete strength. The outcome obtained showed a ductile failure when un-corroded reinforced concrete demonstrates several bending-induced cracks transfer to the steel reinforcement. Moreover, the outcome also showed a brittle failure when wider but fewer transverse cracks occurred under bending loads. Sustained loading as well as initial pre-cracked condition during the corrosion development have shown to have significant impact on the corrosion behavior of concrete properties. Moreover, greater porosity was generally associated with lower compressive, flexural, and tensile strength. Higher cement grade, on the other hand, resulted in lower reduction in concrete strength. This finding highlighted the critical role of cement strength grade in determining the mechanical properties of concrete.

Signs, Symptoms and Complications of Non-Hodgkin's Lymphoma According to Grade and Stage in South Iran

  • Dehghani, Mehdi;Haddadi, Sara;Vojdani, Reza
    • Asian Pacific Journal of Cancer Prevention
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    • v.16 no.8
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    • pp.3551-3557
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    • 2015
  • Background: Non-Hodgkin's lymphoma (NHL) is a heterogeneous type of neoplasm of the lymphatic system. To have a more accurate and early diagnosis we need to know signs, symptoms and complications of lymphoma in early stages besides pathology and immunohistochemistry. Materials and Methods: This prospective study included 110 cases of NHL that were followed since February 2012 till November 2013. Biopsies were taken from all the patients besides bone marrow study. Signs and symptoms were categorized into "B" symptoms, general, lymphadenopathy and extranodal involvement and we compared the frequencies by stage and grade. Results: Of 110 cases, 88.9% had B-cell and 11.1% T-cell type with mean age $48.5{\pm}18.6$ years. "B" symptoms and lymphadenopathy were more common in men. Cervical lymphadenopathy was the most common sign (44.8%). and hematologic, bone marrow, bone and neurologic lesions were the most common complications. All complications were more common in males. "B" symptoms were seen mostly in stage III, general signs and symptoms in stage IV, and lymphadenopathy in stage II. Intermediate grade was also the most common in all signs and symptoms. In this study 12 (10.9%) patients had relapse, with neurologic and bone marrow as the most common sites of tumor recurrence. Conclusions: There is a meaningful relationship between male gender for NHL and anemia that can be due in part to higher incidence of bone marrow involvement and stage IV disease in male cases. We also found a strong relationship between low grade NHL and age. On the other hand extranodal involvement is more common in female groups.