• Explosives and Blasting
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• v.11 no.2
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• pp.60-68
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• 1993

The noise and vibration generated by the subway rolling stocks operated along the Seoul Subway Line No.1, 2, 3, and 4 lead to a controversy of pollution problem especially in residential areas. However, there is no data or guide to define the damage or provide adequate protection against such pollutions. The field measurements were made to characterize the noise attenuation due to distance, noise level distribution around the subway track of the aboveground and underground parts of each Line. The assessment criteria and methods are considered in addition to the practical available noise control methods. The noise level measured at Line No. 1 and 3 are less than 60 dB(A) with no pollution problem. Only a part of the aboveground section of Line No.2 and 4 indicates severe noise pollution. The effective boundary of these areas exposed to 70dB (A) noise are within 50m from the track centerline of No.2 line and 25m of No.4 line. The residents file a strong complaints whenever the noise level exceeds the 80dB (A) , and an occasional complaints between 70 to 80 dB(A). The distribution of high level noise of 80 dB(A) occurs within 25m from the track centerline of the overbridge, 12.5m of the short steel bridge, and about loom of the long steel bridge such as Dangsan Bridge. The intermediate noise level of 70 to 80 dB(A) is recorded within 50m from the overbridge, U-type retaining structure, and short steel structure, and 280m from the long steel bridge. The results presented in this paper can be used to understand the characteristics of the noise pollution along the Seoul Subway now In operation, and used as a guide to improve the existing noise pollution problems.

• Journal of the korean academy of Pediatric Dentistry
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• v.31 no.1
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• pp.85-91
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• 2004

The purpose of this study was to observe in vitro pulp chamber temperature rise during composite resin polymerization with various light-curing sources. The kinds of light-curing sources were plasma arc light(P), low heat plasma arc light, traditional low intensity halogen light, low intensity LED(L-LED), and high intensity LED(H-LED). Temperature at the tip of light guide was measured by a digital thermometer using K-type thermocouple. Occlusal cavities$(2{\times}2{\times}1.5mm)$ were so prepared in extracted human premolars as to the remaining dentin thickness was 1mm. Dentin adhesive was applied to all cavities. Experimental groups consisted of no base group, ionomer glass base group, and calcium hydroxide base group. Temperature before and after resin filling was measured. Temperature at the light guide tip was the highest with P and the lowest L-LED. Temperature before resin filling was the highest with H-LED and the lowest with L-LED. Temperature after resin filling was the highest with H-LED and the lowest with L-P and with L-LED. The lining of base partially reduced the temperature rise.

• Journal of the Korean Society for information Management
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• v.27 no.1
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• pp.229-248
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• 2010

Research has taken priority of many activities in universities and it has eventually brought the heat on research support services of libraries to meet high expectation of university researchers. To identify the major content areas and service methods of research guides serviced through digital libraries of universities, this study investigated research guides of 60 university libraries in North America and Korea. As a result, 13 categories for research guide contents were identified and 5 crucial areas for the contents development were suggested. It also analyzed providing methods of online research guides and communicating methods between librarians and users. Librarians were identified as the prime human resource to develope and manage research guides, which will play an important role in expanding diversity of librarians' roles in the future.

• Journal of Embryo Transfer
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• v.12 no.1
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• pp.111-116
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• 1997

The present study was carried out to produce in vitro fertilized embryos with immature follicular oocytes collected by transvaginal aspiration from Holstein cows. A simple aspiration apparatus consists of two stainless steel tubes, an inner tube (needle holder; 1.2cmdiameter, 55cm long) and an outer tube (1.5cm diameter, 4Scm long), and a hand-operated vacuum pump was used. Under epidural anesthesia, the needle guide was passed into the vagina of the cow to a point next to the cervix. An ovary was placed against the wall of the vagina over the end of the aspiration needle by rectal manipulation. As the needlepassed into the ovary, an assistant was asked to apply vacuum(l00mrnHg) and the ovary was manipulated back and forth in all directions over the needle. When all sites of the ovary was aspirated, the needle was withdrawn and the needle guide was moved to the other side of ovary and the procedure was repeated. When the oocyte aspiration procedure was finished, collected fluid was transported to laboratory. Oocytes surrounded with at least 1 layer of cumulus cells were matured, fertilized and cultured in vitro. The results were as follows; Ninety seven oocytes were collected by transvaginal aspiration from seventeen Holstein cows(5.7 /head). The number of oocytes surrounded with at least 1 layer of cumulus cells were 60(61.9%). Following in vitro maturation, fertilization and culture, the cleavage and development rate to morula+blastocyst were 83.3% and 30.0%, respectively. From this study, transferable in vitro fertilized embryos could be produced with imma- ture follicular oocytes collected by transvaginal aspiration from Holstein cows using a simple aspiration apparatus.

• Transactions of Materials Processing
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• v.20 no.1
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• pp.5-10
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• 2011

The main objective of the present study is to predict the process window of injection-compression molding corresponding to the capability of an injection machine for fabricating 7 inch LGP. The open distance and volume filled after injection stage were found to be two important factors that affect critical requirements such as flow length, injection pressure and clamping force for the process. Process window for the key factors was also predicted by response surface method. As a result, predicted process window for open distance and volume filled after injection stage satisfying the critical requirement with a given injection machine was in the range of 60 ~ 75%, and 104.00 ~ 104.25%, respectively.

• Journal of Magnetics
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• v.17 no.1
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• pp.56-60
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• 2012

This paper presents an analysis and experiment of the flat coil actuator with shorted turn. The flat coil actuator is widely used in high precision products because it has no friction between the moving coil and the guide. A shorted turn and a center pole are placed into the flat coil actuator in order to reduce the inductance of the coil and improve the initial response when the actuator is voltage-driven. Enhanced dynamic performance of the flat coil actuator with shorted turn was demonstrated by simulation and experiment.

• Progress in Medical Physics
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• v.8 no.2
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• pp.67-76
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• 1997

We studied optical behavior of scintillation light generated in NaI(TI) crystal using Monte Carlo simulation method. The simulation was performed for the model of NaI(TI) scintillator (size: 60 mm ${\times}$ 60 mm ${\times}$ 6 mm) using an optical tracking code. The sensitivity as a function of surface treatment (Ground, Polished, Metal-0.95RC, Polished-0.98RC, Painted- 0.98RC) of the incident surface of the scintillator was compared. The effects of NaI(TI) scintillator thickness and the refractive index of light guide optically coupling between the NaI(TI) scintillator and photomultiplier tube (PMT) were simulated. We also evaluated intrinsic position resolution of the system by calculating the spread of scintillation light generated. The sensitivities of the system having the surface treatment of Ground, Polished, Metal-0.95RC, Polished-0.98RC and Painted-0.98RC were 70.9％, 73.9％, 78.6％, 80.1％ and 85.2％, respectively, and the surface treatment of Painted-0.98RC allowed the highest sensitivity. As increasing the thickness of scintillation crystal and light guide, the sensitivity of the system was decreased. As the refractive index of light guide increases, the sensitivity was increased. The intrinsic position resolution of the system was estimated to be 1.2 mm in horizontal and vertical directions. In this study, the performance of NaI(TI)-PMT detector system was evaluated using Monte Carlo simulation. Based on the results, we concluded that the NaI(TI)-PMT detector array is a favorable configuration for small gamma camera imaging breast tumor using Tc-99m labeled radiopharmaceuticals.

• Korean Journal of Radiology
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• v.21 no.7
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• pp.812-828
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• 2020

Objective: To provide an evidence-based guide for the MRI interpretation of complete tumor response after neoadjuvant chemoradiation therapy (CRT) for rectal cancer using visual assessment on T2-weighted imaging (T2) and diffusion-weighted imaging (DWI). Materials and Methods: PubMed MEDLINE, EMBASE, and Cochrane Library were searched on November 28, 2019 to identify articles on the following issues: 1) sensitivity and specificity of T2 or DWI for diagnosing pathologic complete response (pCR) and the criteria for MRI diagnosis; 2) MRI alone vs. MRI combined with other test(s) in sensitivity and specificity for pCR; and 3) tests to select patients for the watch-and-wait management. Eligible articles were selected according to meticulous criteria and were synthesized. Results: Of 1615 article candidates, 55 eligible articles (for all three issues combined) were identified. Combined T2 and DWI performed better than T2 alone, with a meta-analytic summary sensitivity of 0.62 (95% confidence interval [CI], 0.43-0.77; I² = 80.60) and summary specificity of 0.89 (95% CI, 0.80-0.94; I² = 92.61) for diagnosing pCR. The criteria for the complete response on T2 in most studies had the commonality of remarkable tumor decrease to the absence of mass-like or nodular intermediate signal, although somewhat varied, as follows: (near) normalization of the wall; regular, thin, hypointense scar in the luminal side with (near) normal-appearance or homogeneous intermediate signal in the underlying wall; and hypointense thickening of the wall. The criteria on DWI were the absence of a hyperintense signal at high b-value (≥ 800 sec/mm²) in most studies. The specific algorithm to combine T2 and DWI was obscure in half of the studies. MRI combined with endoscopy was the most utilized means to select patients for the watch-and-wait management despite a lack of strong evidence to guide and support a multi-test approach. Conclusion: This systematic review and meta-analysis provide an evidence-based practical guide for MRI assessment of complete tumor response after CRT for rectal cancer.

• YAKHAK HOEJI
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• v.53 no.1
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• pp.25-33
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• 2009

Metabolic syndrome is increasing nowadays and one of causes is obesity. Therefore prevention and treatment of obesity is very important to decrease of Metabolic syndrome. However currently many pharmacotherapy for obesity are popular in Korea and it may be dangerous. The aim of this study is to evaluate the purpose and relevance of obese treatment in two areas (capital & local) of Korea and suggest to guide for the right directions of pharmacotherapy in obesity treatment. We selected and surveyed 90 patients (88 females, 2 males, age of $23{\sim}60$) at random who received a prescription after consulting with a doctor at several clinics of Cheongju-area and Seoul-area, from May thru June, 2007. And we evaluated their prescriptions. In results, only 26.7% were obese (13.3%, 2325), most 73.3% patients were normal (65.6%, 18.5$m^2$). The purpose of treatment was for appearance (38.9%), health (41.1%) or both (18.9%, p<0.01). 94% patients had the past history of obese treatment. Prescriptions were consisted of CNS stimulant, anticonvulsants, antidepressant, laxatives, diuretics, or antianxietics. Obese treatment is very important for health to prevent disease such as Metabolic Syndrome. However it should not be abused. In conclusion, some patients of obese treatment is not relevant to obesity and pharmacist role is important to guide them for the right directions in obesity treatment.

• The Journal of Korean Medicine
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• v.21 no.4
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• pp.16-25
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• 2000

Objective : Acupuncture and Radix Astragali aqua-acupuncture stimuli have long been used to cure human diseases. However, the exact physiological and biochemical mechanisms involved remain undiscovered. Thus, many attempts have been made to show the scientific mechanisms involved. The effects of acupuncture and Radix Astragali aqua-acupuncture, which was known to date, as follow; effective circulation of body blood system and proliferation of leucocytes. Methods : In this study, we have applied acupuncture and Radix Astragali aqua-acupuncture stimuli to mouse on Sinsuhyul, a stimulative point of oriental medicine, to see effects on the expression of cytokine $IL-1{\beta}$. Mice were treated with lipopolysaccharide(LPS) for inflammation induction and then reverse transcriptase-polymerase chain reaction (RT-PCR) using each primer set were performed to trace the amounts of mRNA. Results : 1. $IL-1{\beta}$ was not expressed in LPS-nontreated mice at 15 to 60 min after acupuncture-stimuli. However, expression occurred after 3hrs. 2. $IL-1{\beta}$ was specifically expressed in LPS-treated mice at 30 min after acupuncture-stimuli. 3. $IL-1{\beta}$ was expressed in LPS-nontreated mice at 30 min after Radix Astragali aqua-acupuncture stimuli, however, not expressed at 60, 180 min. 4. $IL-1{\beta}$ was gradually expressed in LPS-treated mice at 15 to 180 min after Radix Astragali aqua-acupuncture stimuli. Conclusions : $IL-1{\beta}$ in LPS-treated mice was more effective than that of LPS-nontreated mice. We are now in the process of elucidating the immunological action mechanism of acupuncture and Radix Astragali aqua-acupuncture stimuli. And cytokine $IL-1{\beta}$ can be used not only as a basis of the effects of acupuncture and Radix Astragali aqua-acupuncture but also as a diagnosis guide through the immunological actions of those.