• Title/Summary/Keyword: Range Safety

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An Analysis of the Instructional State of the Unit 생Small Living Things′ in the Elementary School Science (초등학교 자연과 생작은생물생 단원의 수업 실태 분석)

  • 최도성;최규식;남철우;김정길;김석중;송판섭;한광래;한효의
    • Journal of Korean Elementary Science Education
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    • v.19 no.1
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    • pp.157-170
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    • 2000
  • The purpose of this study is to survey the instructional state of the unit 'Small Living Things' in the Elementary School Science. for this study, 100 teachers were surveyed on teaching-learning practices. More specifically, questions were asked on the degree of accomplishing instruction objectives, frequency of field . study, experimental preparation, alternative instructional methods, amount of preparation, availability of reference books for teachers and availability of information materials on the Kwangju region. Our results show that teachers find the objectives related to the collection of living things for class experiments and the task of growing and observing them the most difficult to accomplish. It was reported that 38% of teachers have actually conducted field trips. The obstacles listed in going out on field study range from lack of knowledge of appropriate places, lack of time, to safety concerns. The most difficult problem in teaching this unit was preparing proper instructional materials, regardless of teacher's gender, career, and interest. Most respondents let children provide the experimental subjects. Teachers with collection experience tend to provide for the experimental materials themselves. Our Analysis also reveals that more than 70% of the respondents do not have adequate knowledge of the species dealt with in the unit. Gender, career, and interest area of the teachers did not make any difference (p< .05). In the case that proper experimental subjects have not been prepared, VTR, textbooks, and charts were reported as the most frequently used alternative instruction aids. The level of content and amount of knowledge contained in this unit were found to be appropriate. Information on instruction materials and experiment-observation were obtained through the teaching manual or periodicals (58%), information materials on the region(20%), and fellow teachers (12%). Reference books for teachers and materials on the region are perceived to be inadequate in order of importance in the areas of preparation method, level-wise learning guide, experimental observation, and information on species covered in text. Overall, it was judged that the highest concern was with obtaining experimental materials, and teacher's reference books and materials on the region need to be reinforced to allow teachers to more fully utilize them. Development and distribution of proper instruction-learning materials to the children's level is also required.

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An Improved Movable 3 photomultiplier (3PM)-γ Coincidence Counter Using Logical Sum of Double Coincidences in β-Channel for Activity Standardization

  • Hwang, Han Yull;Lee, Jong Man
    • Journal of Radiation Protection and Research
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    • v.45 no.2
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    • pp.76-80
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    • 2020
  • Background: To improve the measurement accuracy of liquid-scintillation counting for activity standardization, it is necessary to significantly reduce the background caused by thermal noise or after-pulses. We have therefore improved a movable 3 photomultiplier (3PM)-γ coincidence-counting method using the logical sum of three double coincidences for β events. Materials and Methods: We designed a new data-acquisition system in which β events are obtained by counting the logical sum of three double coincidences. The change in β-detection efficiency can be derived by moving three photomultiplier tubes sequentially from the liquid-scintillation vial. The validity of the method was investigated by activity measurement of 134Cs calibrated at the Korea Research Institute of Standards and Science (KRISS) with 4π(PC)β-γ(NaI(Tl)) coincidence counting using a proportional counter (PC) for the β detector. Results and Discussion: Measurements were taken over 14 counting intervals for each liquidscintillation sample by displacing three photomultiplier tubes up to 45 mm from the sample. The dead time in each β- and γ-counting channel was adjusted to be a non-extending type of 20 ㎲. The background ranged about 1.2-3.3 s-1, such that the contributions of thermal noise or after-pulses were negligible. As the β-detection unit was moved away from the sample, the β-detection efficiencies varied between 0.54 and 0.81. The result obtained by the method at the reference date was 396.3 ± 1.7 kBq/g. This is consistent with the KRISS-certified value of 396.0 ± 2.0 kBq/g within the uncertainty range. Conclusion: The movable 3PM-γ method developed in the present work not only succeeded in reducing background counts to negligible levels but enabled β-detection efficiency to be varied by a geometrical method to apply the efficiency extrapolation method. Compared with our earlier work shown in the study of Hwang et al. [2], the measurement accuracy has much improved. Consequently, the method developed in this study is an improved method suitable for activity standardization of β-γ emitters.

Modified Docetaxel and Cisplatin in Combination with Capecitabine (DCX) as a First-Line Treatment in HER2-Negative Advanced Gastric Cancer

  • Bilici, Ahmet;Selcukbiricik, Fatih;Demir, Nazan;Ustaalioglu, Bala Basak Oven;Dikilitas, Mustafa;Yildiz, Ozcan
    • Asian Pacific Journal of Cancer Prevention
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    • v.15 no.20
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    • pp.8661-8666
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    • 2014
  • Background: Docetaxel and cisplatin in combination with fluorouracil (DCF) regimen is accepted to be one of the standard regimens in the treatment of advanced gastric cancer. However, substantial toxicity has limited its use in daily clinical practice. Therefore, modification of DCF regimens, including introduction of capecitabine has been investigated to improve the safety profiles. In the present study, the efficacy and toxicity of a regimen with a modified dose of docetaxel and cisplatin in combination with oral capecitabine (DCX) was evaluated in untreated patients with HER2-negative advanced gastric cancer. Materials and Methods: Fifty-four patients with HER2-negative locally advanced or metastatic gastric cancer were included in this cohort. Patients received docetaxel $60mg/m^2$ plus cisplatin $60mg/m^2$ (day 1) combined with capecitabine $1650mg/m^2$ (days 1-14) every 3 weeks. Treatment response, survival, and toxicity were retrospectively analyzed. Results: The median age was 54 years (range: 24-76). The majority of patients (70%) had metastatic disease, while 11 patients (21%) had recurrent disease and underwent curative gastrectomy, and 5 patients (9%) had locally advanced disease (LAD). The median number of DCX cycles was 4. There were 28 partial responses and 11 complete responses, with an overall response rate of 72%. Curative surgery could be performed in four patients among five with LAD. At the median follow-up of 10 months, the median progression-free survival (PFS) and overall survival (OS) of the entire cohort of patients were 7.4 and 12.1 months, respectively. Dose modification was done in 12 patients due to toxicity in 8 and noncompliance in 4 patients. The most common hematological toxicity was neutropenia, which occurred at grade 3-4 intensity in 10 of 54 patients (27.7%). Febrile neutropenia was diagnosed only in two cases. Conclusions: DCX regimen offers prominent anti-tumor activity and considered to be effective first-line treatment with manageable toxicity for patients with HER2-negative advanced gastric cancer.

A Case Report of Harpagophyti Radix Pharmacopuncture for the Patient with Breast Cancer Transpered to Spine (유방암의 척추전이 환자에 대한 천수근 약침을 병행한 한의학적 치료 증례 1례)

  • Bae, Young-Hyeon;Lee, Chong-Hwan;Kim, Hae-Sol;Kim, Ho-Sun;Suh, Chang-Yong;Kim, No-Hyeon;Song, Ju-Hyun;Yeom, Seung-Chul
    • The Journal of Churna Manual Medicine for Spine and Nerves
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    • v.10 no.1
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    • pp.117-127
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    • 2015
  • Objectives : Most of pains are important symptoms caused by cancer transpered to spine. Harpagophyti Radix Pharmacopuncture is highly effective in reducing fever, pain, inflammation but was never used to reduce pain from cancer transpered to spine. So I intended to use Harpagophyti Radix Pharmacopuncture to control pain. The purpose of this study is to evaluate the clinical application of Harpagophyti Radix Pharmacopuncture for Bone Metastasis of Breast Cancer and Spinal Stenosis. Methods : We examined patient with Bone Metastasis of Breast Cancer and Spinal Stenosis who admitted Jaseng Korean Medicine Hospital. The patient was treated by Korean Medicine treatment and Harpagophyti Radix Pharmacopuncture. This case was assessed by Numerical Rating Scale(NRS), Oswestry Low Back Pain Disability Index(ODI), Short-Form 36 Health Survey(SF-36), ROM(Range of Movement) and Special Test. Results : In this study, the patient's pain was controlled and NRS, ODI were decreased. I could identify the improvement in life quality from the positive change of SF-36 and also found out that treatment was successful from the improvement of ROM, Special test. Conclusions : Harpagophyti Radix Pharmacopuncture with Korean Medicine treatment for Bone Metastasis of Breast Cancer and Spinal Stenosis was proved to be useful to the pain relief and function recovery, but further research should take place for clear understanding of the exact amount of dosage and safety. Moreover it must be accompanied by long term follow up research.

MR Technology to 4T

  • Vaughan, Thomas
    • Proceedings of the KSMRM Conference
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    • 2003.10a
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    • pp.103-105
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    • 2003
  • After fifteen years of development, Magnetic Resonance (MR) technology for human imaging and spectroscopy is reaching a refined state with FDA approved 3T clinical products from Siemens, GE, and Philips. Broker has cleared CE approval with a 4T system. Varian supports a 4T system platform as well. Shielded magnets are standard at 3T from GE, Oxford, Magnex, and IGC. A shielded 4T whole body magnet is available from Oxford. Stronger switched gradients and dynamic shim coils, desired at any field, areespecially useful at higher static magnetic fields B0. In addition to the higher currents required for higher resolution slice or volume selection afforded by higher SNR, whole body gradient coils will be driven at increasing slew rates to meet the needs of new cardiac applications and other requirements. For example 3T and 4T systems are now being equipped with 2kV, 500A gradient coils and amplifiers capable of generating 4G/cm in 200msec, over a 67+/-cm bore diameter. High field EPI applications require oscillation rates at 1 kHz and higher. To achieve a benchmark 0.2 ppm shim over a 30cm sphere in a high field magnet, at least four stages of shimming need to be considered. 1) A good high field magnet will be built to a homogeneity spec. falling in the range of 100 to 150 ppm over this 30cm spherical "sweet spot" 2) Most modern high field magnets will also have superconducting shim coils capable of finding 1.5 ppm by their adjustment during system installation. 3) Passive ferro-magnetic shimming combined with 4) active, high order room temperature shim coils (as many as five orders are now being recommended) will accomplish 0.2 ppm over the 30cm sphere, and 0.1 ppm over a human brain in even the highest field magnets for human studies. Safety concerns for strong, fast gradients at any B0 field include acoustic noise and peripheral nerve stimulation. One or more of the mechanical decoupling methods may lead to quieter gradients. Patient positioning relative to asymmetric or short gradient coils may limit peripheral nerve stimulation at higher slew rates. Gradient designs combining a short coil for local speed and strength with a longer coil for coverage are being developed for 3T systems. Local gradients give another approach to maximizing performance over a limited region while keeping within the physiologically imposed dB0/dt performance limits.

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Application of ultrasonic energy to enhance capability of soil improving material (지반보강용 주입재의 성능향상을 위한 초음파 에너지의 활용)

  • Moon, Jun-ho;Xin, Zhenhua;Jeong, Ghang-bok;Kim, Young-uk
    • Journal of Korean Tunnelling and Underground Space Association
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    • v.19 no.4
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    • pp.567-576
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    • 2017
  • In a performance-based design, the structural safety is estimated from pre- defined damage states and corresponding damage indices. Both damage states and damage indices are well defined for above-ground structures, but very limited studies have been performed on underground structures. In this study, we define the damage states and damage indices of a cut-and-cover box tunnel which is one of typical structures used in metro systems, under a seismic excitation from a series of inelastic frame analyses. Three damage states are defined in terms of the number of plastic hinges that develop within the structure. The damage index is defined as the ratio of the elastic moment to the yield moment. Through use of the proposed index, the inelastic behavior and failure mechanism of box tunnels can be simulated and predicted through elastic analysis. In addition, the damage indices are linked to free-field shear strains. Because the free-field shear strain can be easily calculated from a 1D site response analysis, the proposed method can be readily used in practice. Further studies are needed to determine the range of shear strains and associated uncertainties for various types of tunnels and site profiles. However, the inter-linked platform of damage state - damage index - shear wave velocity - shear strain provides a novel approach for estimating the inelastic response of tunnels, and can be widely used in practice for seismic designs.

Evaluation of field applicability for grouting method using self-healing grout material (자기치유 물질을 이용한 그라우팅공법의 현장적용성 평가)

  • Choi, Yong-Sung;Kim, Byoung-Il;Yoo, Wan-Kyu;Lee, Jae-Dug;Choi, Yong-Ki
    • Journal of Korean Tunnelling and Underground Space Association
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    • v.22 no.5
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    • pp.485-500
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    • 2020
  • Due to various advantages such as small facilities, ease of construction and so on, the grouting technology which is widely used in construction field has developed remarkably compared with the past. However, the efforts to improve the homogeneity of quality, long-term durability and environmental problems have been continued. In recent years, new grouting method has been developed in order to solve problems such as low strength, durability and leaching phenomenon of liquid glass (sodium silicate) grouting material in Korea. A newly developed method integrates the injection material with the ground by the self-healing material of crystallization growth type. For this reason, it is known that improvement of the durability and water quality of the ground, prevention of leaching, and environment friendliness can be expected. The present study applied a newly developed method to test sites and verified its effect such as injection range, improvement effect, waterproofing performance and so on. Standard penetration test, field permeability test, borehole shear test, pressuremeter test and pH test were conducted, and the results were compared between before and after developed method application. As results of tests, the field applicability and improvement effect of developed method were proved to be excellent.

Phase II Study on Pemetrexed-based Chemotherapy in Treating Patients with Metastatic Gastric Cancer not Responding to Prior Palliative Chemotherapy

  • Wei, Guo-Li;Huang, Xin-En;Huo, Jie-Ge;Wang, Xiao-Ning;Tang, Jin-Hai
    • Asian Pacific Journal of Cancer Prevention
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    • v.14 no.5
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    • pp.2703-2706
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    • 2013
  • Purpose: This study was to determine the efficacy and safety of pemetrexed based chemotherapy in treating patients with metastatic gastric cancer who failed to respond to first and (or) second line chemotherapy. Patients and Methods: Metastatic gastric cancer patients who failed first and (or) second line chemotherapy, were enrolled. All patients were recruited from Jiangsu Cancer Hospital & Research Institute, and were treated with pemetrexed $500mg/m2$ (intravenous; on day 1), and a platinum (or irinotecan) every 3 weeks until disease progression, or intolerable toxicity. Evaluation on efficacy was conducted after two cycles of chemotherapy using the Response Evaluation Criteria for Solid Tumors. Toxicity was recorded according to National Cancer Institute Common Terminology Criteria for Adverse Events version 3.0. Results: From Jun 2011 to May 2013, 23 patients were enrolled. All eligible 23 patients completed at least 2 cycles of chemotherapy with pemetrexed based chemotherapy, and were evaluable. Their median age was 55 years (range 40 to 78 years). Seventeen patients were male and 6 female. Three patients (13%) achieved partial response, five patients (22%) stable, 15 patients (65%) with disease progression, and none with complete response. Grade 2 neutrophil suppression occurred in 4.3%, grade 3 in 13% of patients, and no grade 4 was reported. Thrombocytopenia was encountered as follows: 4.3% grade 2, 4.3% grade 3 and 4.3% grade 4. Incidence of anemia was 34.8% in grade 2, 8.7% grade 3 and 0% grade 4. Only 4.3% of patients required packed red blood cell infusion. Elevated transaminase were 4.3% in grade 2 and 0% in grade 3 or 4. Other toxicity included oral mucositis. Conclusions: Pemetrexed based chemotherapy is mildly effective in treating patients with metastatic gastric cancer with tolerable toxicity.

Residual Characteristics of Insecticide Dinotefuran in Asparagus under Greenhouse Condition (시설재배 아스파라거스 중 살충제 dinotefuran의 잔류특성)

  • Boo, Kyung Hwan
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.19 no.6
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    • pp.375-381
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    • 2018
  • This study was performed to investigate the residual characteristics of the insecticide dinotefuran in asparagus under greenhouse conditions from July to August and consequentially to obtain basic data for guidelines on the safe use of this pesticide in asparagus. Residues of dinotefuran in young stem of asparagus before and after growing mother stem were analyzed from samples collected at 0, 1, 3, 5, and 7 days after single application of a commercial formulation of dinotefuran (wettable powder, 10%) at the recommended dose (2,000 times dilution). The residue of dinotefuran in young stem of asparagus was analyzed by HPLC-UVD, and recovery of dinotefuran in young stem was tested at 0.5 and 1.0 mg/kg concentrations. As a result, the limit of quantitation (LOQ) of dinotefuran was 0.01 mg/kg, and the recovery of dinotefuran was in the range of 83.3-94.0% with a coefficient of variation less than 10%. Residues of dinotefuran in young stem of asparagus before and after growing the mother stem were lower than the tentative limit (0.05 mg/kg) from 5 and 3 days after single application, respectively. Based on these results, single application of dinotefuran (wettable powder, 10%) at the recommended dose at 7 days before harvest would have no deleterious effects on safety issues concerning pesticide residue. This result might provide basic information to construct guidelines for the safe use of dinotefuran in asparagus.

Development of CCTV Cooperation Tracking System for Real-Time Crime Monitoring (실시간 범죄 모니터링을 위한 CCTV 협업 추적시스템 개발 연구)

  • Choi, Woo-Chul;Na, Joon-Yeop
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.20 no.12
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    • pp.546-554
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    • 2019
  • Typically, closed-circuit television (CCTV) monitoring is mainly used for post-processes (i.e. to provide evidence after an incident has occurred), but by using a streaming video feed, machine-based learning, and advanced image recognition techniques, current technology can be extended to respond to crimes or reports of missing persons in real time. The multi-CCTV cooperation technique developed in this study is a program model that delivers similarity information about a suspect (or moving object) extracted via CCTV at one location and sent to a monitoring agent to track the selected suspect or object when he, she, or it moves out of range to another CCTV camera. To improve the operating efficiency of local government CCTV control centers, we describe here the partial automation of a CCTV control system that currently relies upon monitoring by human agents. We envisage an integrated crime prevention service, which incorporates the cooperative CCTV network suggested in this study and that can easily be experienced by citizens in ways such as determining a precise individual location in real time and providing a crime prevention service linked to smartphones and/or crime prevention/safety information.