• Korean Journal of Construction Engineering and Management
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• v.17 no.5
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• pp.3-12
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• 2016

Recently government is set to expand its policy to promote technical proposal tendering in a dimension of technical competitiveness reinforcement. Because a variety of complicated techniques are applied in technical proposal tendering and variables could be occurred in terms of cost, schedule, constructability and others when techniques are reflected on design document collaboration management among participants is considered insignificantly. So the research would determine primary management factors and presents management direction for collaboration among participants. First action for this is categorization of hindrance factors to collaboration into five factors as 'Poor work processing', 'Communication cap among participants', 'Lack of understanding about technical proposal tendering', 'Difficulty of decision making' and 'Insufficiency in managing the work data'. Second correlation analysis is conducted between the categorized factors and participants according to tasks in technical proposal tendering to figure out the correlation degree of variables. If there is a strong correlation between variables, hindrance factor in that case regarded primary management factor to collaboration and finally management direction is presented at each task.

• Journal of Bio-Environment Control
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• v.20 no.4
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• pp.297-303
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• 2011

The contents of capsaicinoid, free sugars and organic acids of six varieties of Korean hot pepper, Supermanita, Dokyacheongcheong, Shinseokyeoi, Wangdaebak, Hanbando, and Chungyang, were measured. The sensory evaluations of its extracts were compared in order to investigate the indirect effect or reaction of the composition of taste components on sensory acceptability of Korean hot pepper. The contents of capsaicinoid were considerably from $37.8mg{\cdot}100g^{-1}$ to $164.1mg{\cdot}100g^{-1}$, and the contents of free sugars were from 9.3% to 18.2%, and the contents of organic acids were from 8.1% to 14.7% in Korean hot peppers. Although the pungent sensory evaluation of water extract of pepper powder was completely accordant with instrumental analysis result of capsaicinoid contents, they did not show a significant relationship to the sensory of taste. Multiple regression with capsaicinoid (CAP), total sugars (TS) and total organic acid (TOA) contents increased the correlation coefficient for sensory of taste to r = 0.927 and the coefficient of determination for them to $R^2=0.906$. However, we suggest the more efficient function for it which is composed of two independent variables only. As the result, a regression equation of Y = 0.69 X + 0.11 with $R^2=0.884$ was obtained for quantitative analysis of sensory evaluation of pepper taste by two factors between capsaicinoid and total free sugar.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.31 no.2D
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• pp.323-334
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• 2011

In this study, we performed the residual geoid modeling using the FFT and LSC methods in context of application of R-R (Remove and Restore) technique as a general technique for gravimetric geoid model in order to propose the effective way of geoid determination in Korea. For this, a number of data compiled for residual geoid modeling by the multi-band spherical FFT method with Stoke's formula and LSC method as known as statistical method. The geometric geoidal heights obtained from 503 GPS/Levelling data were used for inducing the various elements and proper computation process which should be considered for improving the accuracy of residual geoid modeling. Finally, we statistically compared the results of residual geoid heights between FFT and LSC methods and reviewed then the proper way of residual geoid modeling to the region of Korea. As the results of comparison, LSC method is not suitable for residual geoid modeling in Korea due to the noise and lack of gravity observations and the effects of local characteristics, while FFT method by applying Stokes' integral with proper cap size and modified kernel which provides the better accuracy of residual geoid heights up to 10 cm more than those of LSC method.

• Smart Structures and Systems
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• v.20 no.5
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• pp.549-562
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• 2017

The US railroad network carries 40% of the nation's total freight. Railroad bridges are the most critical part of the network infrastructure and, therefore, must be properly maintained for the operational safety. Railroad managers inspect bridges by measuring displacements under train crossing events to assess their structural condition and prioritize bridge management and safety decisions accordingly. The displacement of a railroad bridge under train crossings is one parameter of interest to railroad bridge owners, as it quantifies a bridge's ability to perform safely and addresses its serviceability. Railroad bridges with poor track conditions will have amplified displacements under heavy loads due to impacts between the wheels and rail joints. Under these circumstances, vehicle-track-bridge interactions could cause excessive bridge displacements, and hence, unsafe train crossings. If displacements during train crossings could be measured objectively, owners could repair or replace less safe bridges first. However, data on bridge displacements is difficult to collect in the field as a fixed point of reference is required for measurement. Accelerations can be used to estimate dynamic displacements, but to date, the pseudo-static displacements cannot be measured using reference-free sensors. This study proposes a method to estimate total transverse displacements of a railroad bridge under live train loads using acceleration and tilt data at the top of the exterior pile bent of a standard timber trestle, where train derailment due to excessive lateral movement is the main concern. Researchers used real bridge transverse displacement data under train traffic from varying bridge serviceability levels. This study explores the design of a new bridge deck-pier experimental model that simulates the vibrations of railroad bridges under traffic using a shake table for the input of train crossing data collected from the field into a laboratory model of a standard timber railroad pile bent. Reference-free sensors measured both the inclination angle and accelerations of the pile cap. Various readings are used to estimate the total displacements of the bridge using data filtering. The estimated displacements are then compared to the true responses of the model measured with displacement sensors. An average peak error of 10% and a root mean square error average of 5% resulted, concluding that this method can cost-effectively measure the total displacement of railroad bridges without a fixed reference.

• Journal of Ginseng Research
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• v.44 no.5
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• pp.697-703
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• 2020

Background: GS-3K8 and GINST, both of which are modified ginseng extracts, have never been examined in terms of their effectiveness for the prevention of acute respiratory illness (ARI) in humans. We conducted a pilot study to assess the feasibility of performing a large-scale, randomized, controlled trial. Methods: This study was a randomized, double-blind, placebo-controlled, pilot study at a single center from October 2014 to March 2015. The 45 healthy applicants were randomly divided into the GS-3K8 (n = 15), GINST (n = 15), and placebo groups (n = 15). The study drug was administered as a capsule (500 mg/cap and 3000 mg/day). GS-3K8 contained 6.31 mg/g of Rg1, 15.05 mg/g of Re, 30.84 mg/g of Rb1, 15.02 mg/g of Rc, 12.44 mg/g of Rb2, 6.97 mg/g of Rd, 1.59 mg/g of Rg3, 3.25 mg/g of Rk1, and 4.84 mg/g of Rg5. GINST contained 7.54 mg/g of Rg1, 1.87 mg/g of Re, 5.42 mg/g of Rb1, 0.29 mg/g of Rc, 0.36 mg/g of Rb2, 0.70 mg/g of Rd, and 6.3 mg/g of compound K. The feasibility criteria were the rates of recruitment, drug compliance, and successful follow-up. The primary clinical outcome measure was the incidence of ARI. The secondary clinical outcome measures were the duration of symptoms. Results: The rate of recruitment was 11.3 participants per week. The overall rate of completed follow-up was 97.8%. The mean compliance rate was 91.64 ± 9.80%, 95.28 ± 5.75%, and 89.70 ± 8.99% in the GS-3K8, GINST, and placebo groups, respectively. The incidence of ARI was 64.3% (9/14; 95% confidence interval [CI], 31.4-91.1%), 26.7% (4/15; 95% CI, 4.3-49.0%), and 80.0% (12/15; 95% CI, 54.8-93.0%) in the GS-3K8, GINST, and placebo groups, respectively. The average days of symptoms were 3.89 ± 4.65, 9.25 ± 7.63, and 12.25 ± 12.69 in the GS-3K8, GINST, and placebo groups, respectively. Conclusion: The results support the feasibility of a full-scale trial. GS-3K8 and GINST appear to have a positive tendency toward preventing the development of ARI and reducing the symptom duration. A randomized controlled trial is needed to confirm these findings.

• Elastomers and Composites
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• v.34 no.2
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• pp.156-176
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• 1999

Rubber chemicals such as accelerators, antidegradants, vulcanizing agents, processing agents and retarders are very important to the production and protection of tires and rubber goods. The use of accelerators and antidegradants are evaluated in various tire components. This paper will focus on how to vulcanize tires economically and maintain the physical properties of each tire component without severe degradation due to oxygen, heat and ozone. Also, new non-nitrosoamine accelerators and non-staining antiozonants will be discussed. Lastly, the future requirements of antidegradants and accelerators in the tire industry will be reviewed. Tires have been vulcanized with Sulfenamides as primary accelerators and either Guamdine's or Thiurams as secondary accelerators to achieve proper properties at service conditions. However, interior components such as the carcass can be vulcanized with Thiazoles as a primary accelerator to cure faster than the external components. Using the combination of Sulfenamide with secondary accelerators in a tire tread compound and the combination of a Thiazole and Guanidine in a carcass compound will be presented with performance data. Uniroyal Chemical and another Rubber Chemical Manufacturer have developed, "Tetrabenzyl Thiuram Disulfide," (TBzTD) as a non-Nitrosoamine accelerator, which could replace Nitrosoamine generating Thiurams. This new accelerator has been evaluated in a tread compound as a secondary accelerator. Also, Flexsys has developed N-t-butyl-2-benzothiazole Sulfenamide (TBSI) as a non-Nitrosoamine accelerator which could replace 2-(Morpholinothio) -benzothiazole (MBS), a scorch delayed Sulfendamide accelerator. TBSI has been evaluated in a Natural Rubber (NR) belt skim compound vs. MBS. An optimum low rolling resistant cure system has been developed in a NR tread with Dithiomorpholine (DTDM). Also, future requirements for developing accelerators will be discussed such as the replacement of DTDM and other stable crosslink systems. Antidegradants are divided into two different types for use in tire compounds. Internal tire compounds such as apex, carcass, liner, wire breaker, cushion, base tread and bead compounds are protected by antioxidants against degradation from oxygen and heat due to mechanical shear. The external components such as sidewall, chafer and cap tread com-pounds are protected from ozone by antiozonants and waxes. Various kinds of staining and non-staining antioxidants have been evaluated in a tire carcass compound. Also, various para-phenylene diamine antiozonants have been evaluated in a tire sidewall compound to achieve the improved lifetime of the tire. New non-staining antiozonants such as 2, 4, 6-tris-(N-1, 4-dimethylpentyl-p-phenylene diamine) 1, 3, 5 Trizine (D-37) and un-saturated Acetal (AFS) will be discussed in the tire sidewall to achieve better appearance. The future requirements of antidegradants will be presented to improve tire performance such as durability, better appearance and longer lasting tires.

• Publications of The Korean Astronomical Society
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• v.25 no.4
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• pp.129-139
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• 2010

The Cowherd Star and the Weaving Maid Star have been famous stars in East Asian countries. Nowadays Altair is defined to be the Cowherd Star in public materials including science books, mass media, public outreach programs, and movies played in public planetariums and science museums. However, in astronomical books and star-charts in history, the Cowherd Big Star (牽牛大星) has been known to be Dabih or $\beta$ Cap in the constellation Capricorn, and the asterism Cowherd consists of six stars including Dabih. Since the same title is given to the different objects simultaneously, considerable misunderstanding and confusion among the public have occurred. In this paper we consider this problem in two aspects. One aspect is which star has been defined to be the Cowherd Star in ancient literatures; the other is which stars were regarded as the Cowherd or the Cowherd Star in the historical records of occultation or conjunction in History of Koryo, Annals of the Choson Dynasty, and Daily Records of Royal Secretariat of the Choson Dynasty. As a result, we see that Altair has been regarded as the Cowherd Star in folklore and literature, but Dabih has been defined to be the Cowherd Big Star in astronomical works. An explanation proposed by previous researchers on the reason why such double meanings have been appeared is introduced. In the explanation, the fact that the Altair was defined as the Cowherd Star in ancient times had not been handed over properly, and the name of Cowherd was later put to the Dabih and its surrounding five stars to form one of 28 lunar lodges. Based upon these facts, we suggest the following ideas: (1) Altair should be introduced to be the Cowherd Star in public-friendly programs, and Dabih should be noticed to be the Cowherd Big Star in the field of history of astronomy. Dabih should be added as the astronomical Cowherd Big Star in academic books such as a dictionary of astronomical terminology. (2) The Korean pronunciation for Altair should be al-tear instead of al-tairu in accordance with the definition in the astronomical terminology dictionary compiled by the Korean Astronomical Society.

• The Korean Journal of Malacology
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• v.26 no.2
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• pp.185-188
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• 2010

The Web-based the genus Haliotis SNP database was constructed on the basis of Intel Server Platform ZSS130 dual Xeon 3.2 GHz cpu and Linux-based (Cent OS) operating system. Haliotis related sequences (2,830 nucleotide sequences, 9,102 EST sequences) were downloaded through NCBI taxonomy browser. In order to eliminate vector sequences, we conducted vector masking step using cross match software with vector sequence database. In addition, poly-A tails were removed using Trimmest software from EMBOSS package. The processed sequences were clustered and assembled by TGICL package (TIGR tools) equipped with CAP3 software. A web-based interface (Haliotis SNP Database, http://www.haliotis.or.kr) was developed to enable optimal use of the clustered assemblies. The Clustering Res. menu shows the contig sequences from the clustering, the alignment results and sequences from each cluster. And also we can compare any sequences with Haliotis related sequences in BLAST menu. The search menu is equipped with its own search engine so that it is possible to search all of the information in the database using the name of a gene, accession number and/or species name. Taken together, the Web-based SNP database for Haliotis will be valuable to develop SNPs of Haliotis in the future.

• Nuclear Engineering and Technology
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• v.49 no.1
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• pp.54-70
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• 2017

The accumulator is a passive safety injection device for emergency core cooling systems. As an important safety feature for providing a high-speed injection flow to the core by compressed nitrogen gas pressure during a loss-of-coolant accident (LOCA), the accumulator injects its precharged nitrogen into the system after its coolant has been emptied. Attention has been drawn to the possible negative effects caused by such a nitrogen injection in passive safety nuclear power plants. Although some experimental work on the nitrogen injection has been done, there have been no comparative tests in which the effects on the system responses and the core safety have been clearly assessed. In this study, a new thermal hydraulic integral test facility-the advanced core-cooling mechanism experiment (ACME)-was designed and constructed to support the CAP1400 safety review. The ACME test facility was used to study the nitrogen injection effects on the system responses to the small break loss-of-coolant accident LOCA (SBLOCA) transient. Two comparison test groups-a 2-inch cold leg break and a double-ended direct-vessel-injection (DEDVI) line break-were conducted. Each group consists of a nitrogen injection test and a nitrogen isolation comparison test with the same break conditions. To assess the nitrogen injection effects, the experimental data that are representative of the system responses and the core safety were compared and analyzed. The results of the comparison show that the effects of nitrogen injection on system responses and core safety are significantly different between the 2-inch and DEDVI breaks. The mechanisms of the different effects on the transient were also investigated. The amount of nitrogen injected, along with its heat absorption, was likewise evaluated in order to assess its effect on the system depressurization process. The results of the comparison and analyses in this study are important for recognizing and understanding the potential negative effects on the passive core cooling performance caused by nitrogen injection during the SBLOCA transient.

• The Journal of the Petrological Society of Korea
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• v.7 no.1
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• pp.1-14
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• 1998

Dangsanbong volcano, which is located on the coast of the western promontory of Cheju Island, occurs in such a regular pattern on the sequences which represent an excellent example of an eruptive cycle. The volcano comprises a horseshoe-shaped tuff cone and a younger nested cinder cone on the crater floor, which are overlain by a lava cap at the top of the cinder cone, and wide lava plateau in the moat between two cones and in the northern part. The volcanic sequences suggest volcanic processes that start with Surtseyan eruption, progress through Strombolian eruption and end with Hawaiian eruption, and then are followed by rock fall from sea cliff of the tuff cone and by air fall from another crater. It is thought that the eruptive environments of the tuff cone could be mainly emergent because the present cone is located on the coast, and standing body of sea water could play a great role. It is thought that the now emergent part of the tuff cone was costructed subaerially because there is no evidence of marine reworking. The emergent tuff cone is characterized by distinctive steam-explosivity that results primarily from a bulk interaction between rapidly ascending magma and external water. The sea water gets into the vent by flooding accross or through the top or breach of northern tephra cone. Dangsanbong tuff cone was constructed from Surtseyan eruption which went into with tephra finger jetting explosion in the early stage, late interspersed with continuous upruch activities, and from ultra-Surtseyan jetting explosions producting base surges in the last. When the enclosure of the vent by a long-lived tephra barrier would prevent the flooding and thus allow the vent to dry out, the phreatomagmatic activities ceased to transmit into magmatic activity of Strombolian eruption, which constructed a cinder cone on the crater floor of the tuff cone Strombolian eruption ceased when magma in the conduit gradually became depleted in gas. In the Dangsanbong volcano, the last magmatic activity was Hawaiian eruption which went into with foundation and effusion of basalt lava.