• Korean journal of applied entomology
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• v.51 no.1
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• pp.9-18
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• 2012

The size of infective $Steinernema$ $arenarium$ juveniles is variable and ranges from 724 to 1408 ${\mu}m$. Effects of harvest time and infective juvenile size on pathogenicity, development, and reproduction were examined in the last instar of the great wax moth, $Galleria$ $mellonella$. Harvest time of infective juveniles (IJs) of $S.$ $arenarium$ affected pathogenicity. IJs harvested at the 10th day from trapping were more pathogenic than those harvested the 3rd day from trapping. Mortality of $G$. mellonella also depending on harvest time, $i.e$, 100% died within 48h when IJs were harvested at the 10th day, without relation to size. However, mortality was 40% in the small size group (SSG) compared with 18% in the large size group (LSG) within 48h when IJs were harvested at the 3rd day. Establishment of $S.$ $arenarium$ within the host was different depending on IJ size. The number of established IJs was 1.8 in the SSG, 3.3 in the LSG, and 3.2 in the mixed size group (MSG) when IJs were harvested at the 3rd day, and 5.3 in the SSG, 7.4 in the LSG, and 7.6 in the MSG when IJs were harvested at the 10th day. The length of the female adult was 7,070.5 ${\mu}m$ in the SSG and 7,893.9 ${\mu}m$ in the LSG and that of the male was 1,460.5 ${\mu}m$ in the SSG and 1,688.2 ${\mu}m$ in the LSG when IJs were harvested at the 3rd day. The length of the female adult was 7,573.6 ${\mu}m$ in the SSG and 8,305.4 ${\mu}m$ in the LSG and that of the male adult was 1,733.4 ${\mu}m$ in the SSG and 1,794.4 ${\mu}m$ in the LSG when IJs were harvested at the 10th day. Harvest time and size of IJs did not influence numbers of progeny or size of IJS.

• Journal of Oral Medicine and Pain
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• v.32 no.3
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• pp.337-346
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• 2007

This study aimed to evaluate a relation of bruxism with clinical effects of botulinum toxin type A(BTX-A) injection. 5 bruxers and 5 nonbruxers with bilateral masseter hypertrophy were participated in this study. After injecting 25 unit of BTX-A(Allergen Inc, $Botox^{(R)}$) into each masseter muscle, the thickness of masseter(Mm) and anterior temporalis(Ta) muscles was measured by ultrasonography and the maximum bite force was evaluated during a 9-month period. Self-estimation on the recovery of occlusal force during mastication was done as well. Regardless of presence of bruxsim, all subjects showed significantly reduced Ms thickness(p<0.001) and maximum bite force at $1^{st}$ molars(p=0.027) with their peak at 3 months after injection, which then started to return. No significant difference was observed in Ta thickness and the bite force at the central incisors. While self-estimated occlusal force was the least at 2 weeks after injection and then rapidly returned to the baseline level with full recovery at the time of 6 to 9 months after injection, the maximum bite force measured by bite force recorder did not recover the original value, particularly in the nonbruxer group. It is assumed that nocturnal bruxism can influence recovery of atrophic masseter and decreased occlusal force due to BTX-A injection. These findings suggest a need of occlusal appliance to control bruxism or clenching habit for longer clinical effect of BTX-A injection.

• Journal of the Korean Society of Food Science and Nutrition
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• v.35 no.10
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• pp.1371-1377
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• 2006

Gene polymorphisms that are associated with sodium homeostasis in the body, such as $\alpha-adducin$ (ADDI, Gly460Trp), angiotensinogen (AGT, Met235Thr), and angiotensin converting enzyme (ACE, Ins/Del) may increase the risk for the development of hypertension. The purpose of this study was to elucidate the relationship between the singular and combined effects of ADD1, AGT, ACE genotypes, and blood pressure in elderly population. Moreover, we examined the interaction of sodium intake and polymorphisms of aforementioned genes and their effects on blood pressure. Among one hundred and nine female subjects, aged 60 and over (mean 75.9 yr), the major alleles for ADD1, AGT, and ACE polymorphisms in the studied population were Gly (66.1%), Thr (64.2%), Ins (83.5%), respectively. Analysis on the combined effects of genetic variation showed that subjects who were both ADD1 Trp/Trp and ACE Del/Del homozygotes had significantly higher systolic blood pressure (p=0.01). Similarly, ACE Del/Del homozygotes who had AGT Met allele had significantly higher diastolic blood pressure (p<0.001). However, in single-gene analyses, no association was found between any specific genotype and blood pressure. In subjects with low sodium intake, ADD1 Trp/Trp homozygotes had significantly higher systolic blood pressure than subjects who had ADD1 Gly allele (138 mmHg vs. 127 mmHg, p=0.03). There was no difference in blood pressure between ADD1 Trp/Trp and ADD1 Gly/Gly or Gly/Trp, in subjects with high sodium intake. In summary, this study shows that interactions between the ADD1, AGT and ACE genes influence systolic and diastolic blood pressure in elderly subjects, and dietary sodium intake can modulate the effects of ADD1 Gly460Trp polymorphisms on systolic blood pres sure.

• Journal of the East Asian Society of Dietary Life
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• v.22 no.1
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• pp.133-146
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• 2012

University dining services have received less attention than commercial food services or other institutional food services. Marketing practitioners and researchers recognize the major impact that perceived value has on consumer behavior. The mediating role of value has not been verified in relation to satisfaction in university dining establishments, including Korea. This study intends to investigate the relationships among value, satisfaction and revisit intention of university dining attributes. This study also examines whether university dining service attributes dimensions influence value. Further, this study verifies the role of value as a mediator in the formation of customer satisfaction and revisit intention. Structural Equation Modeling has been applied to the collected data from students of three universities in Korea. The study resulted in that university dining attributes, such as food, menu and convenience, positively affected value of the university dining services. Further analysis with examination of indirect effects confirmed the positive impact of value on satisfaction in university dining services. This study verified the mediating role of value on satisfaction as student's satisfaction is enhanced through the elevation of value of university food services. Enhanced satisfaction via value also led to improvement in revisit intention. This study contributes to the academia by verifying the mediating role of value in the formation of customer satisfaction in a university dining context. This study also offers practical implications to the industry, such as suggestions on developing strategies for value-added products and services to the university dining establishments. This value research for university dining services is also meaningful by triggering future research on market segmentation, product differentiation and positioning policies. In the long run, improving value and satisfaction with university dining services need to be realized to enhance overall college experiences and other competitive advantages, such as student recruitment and enrollment, student academic evaluations, and university reputation.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.12 no.4
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• pp.145-157
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• 2017

SMEs play an important role in the domestic economy. Regarding competency to respond flexibly to unpredictable changes, agility of SMEs is more emphasized. Entrepreneurship orientation is an important factor in the source of SMEs that enable such competency. Entrepreneurial orientation refers to the tendency of a CEO or a member of a corporation to be innovative, risk-taking, and active in the face of various market opportunities. In other words, it refers to the tendency to be expressed in the activities of the entire company without regard to specific technologies or industries. Entrepreneurial orientation has a direct or indirect effect on business performance. Therefore, in this study, we conducted theoretical and empirical studies on the effect of entrepreneurial orientation of SME managers on business performance. Research hypotheses were derived through theoretical research. We focused on the mediating effect of innovation activity and tried to identify the mechanism that entrepreneurial orientation leads to business performance through product innovation and service innovation activity. We investigated whether innovativeness, proactiveness, and risk-taking, which are sub-variables of entrepreneurial orientation, affect business performance through product innovation and service innovation. We conducted a survey of SMEs in Busan and Kyungnam regions to examine the research hypotheses. The results show that product innovation and service innovation have mediating effects. The results of the study are as follows. Product innovation has mediating effect of innovativeness and risk-taking on business performance. Service innovation has been found to mediate innovativeness, proactiveness, and risk-taking on business performance. There was a difference in the mediation effect between the two innovations. Product innovation showed a low mediating effect and a large direct effect. On the other hands, service innovation is relatively more mediating than product innovation. The implications of the research results are derived in relation to the essential differences between product innovation and service innovation. Limitations of the study and directions for future research are presented.

• The Journal of Korean Academy of Prosthodontics
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• v.47 no.2
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• pp.125-135
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• 2009

Statement of problem: Loosening or fracture of the abutment screw is one of the common problems related to the dental implant. Generally, in order to make the screw joint stable, the preload generated by tightening torque needs to be increased within the elastic limit of the screw. However, additional tensile forces can produce the plastic deformation of abutment screw when functional loads are superimposed on preload stresses, and they can elicit loosening or fracture of the abutment screw. Therefore, it is necessary to find the optimum tightening torque that maximizes a fatigue life and simultaneously offer a reasonable degree of protection against loosening. Purpose: The purpose of this study was to present the influence of tightening torque on the implant-abutment screw joint stability with the 3 dimensional finite element analysis. Material and methods: In this study, the finite element model of the implant system with external butt joint connection was designed and verified by comparison with additional theoretical and experimental results. Four different amount of tightening torques(10, 20, 30 and 40 Ncm) and the external loading(250 N, $30^{\circ}$) were applied to the model, and the equivalent stress distributions and the gap distances were calculated according to each tightening torque and the result was analyzed. Results: Within the limitation of this study, the following results were drawn; 1) There was the proportional relation between the tightening torque and the preload. 2) In case of applying only the tightening torque, the maximum stress was found at the screw neck. 3) The maximum stress was also shown at the screw neck under the external loading condition. However in case of applying 10 Ncm tightening torque, it was found at the undersurface of the screw head. 4) The joint opening was observed under the external loading in case of applying 10 Ncm and 20 Ncm of tightening torque. 5) When the tightening torque was applied at 40 Ncm, under the external loading the maximum stress exceeded the allowable stress value of the titanium alloy. Conclusion: Implant abutment screw must have a proper tightening torque that will be able to maintain joint stability of fixture and abutment.

• Journal of the Korean Society of Marine Environment & Safety
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• v.19 no.5
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• pp.467-475
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• 2013

In order to seize quantitative materials as part of studies on measures for oil pollution prevention and control, the statistics of oil pollution incidents in Korean coastal waters for 10 years from 2003 to 2012 were analyzed with relation to the number of oil spills and the volume of oil spilt according to causes, sources and sea areas of spills. Total number and total volume of oil spills for 10 years were found to be 2,833 cases and 17,877 kL, respectively. 50.4 %(1,429 cases) of total number of oil spills were caused by negligence, although oil spillage due to negligence was 294 kL(1.7 %). While oil spillage caused by marine accidents was 17,400 kL(97.3 %), marine accidents accounted for 27.9 %(790 cases) of total number of oil spills. While negligence had a great influence on the number of oil spills, marine accidents had a huge impact on the amount of oil spilt. Fishing boats accounted for 42.7 %(1,210 cases) of the number of oil spills, and although oil tankers accounted for 9.2 %(261 cases) of the number of oil spills, oil spillage from oil tankers was 15,488kL(86.7 %). It means that oil tankers such as VLCC or ULCC may be the main sources of major oil spills and a few very large spills are responsible for a high percentage of the amount of oil spilt. While the number of oil spill incidents was closely related to the accidents of fishing boats, the volume of oil spilt was greatly affected by the major oil spill incidents of oil tankers such as M/T Hebei Spirit. The number and volume of oil spills were shown to be 1,613 cases(56.9 %) and 3,804 kL(21.3 %) in South Sea, 700 cases(24.7 %) and 13,501 kL(75.5 %) in West Sea, and 520 cases(18.2 %) and 572 kL(3.2 %) in East Sea of Korea, respectively. The highest number of oil spills was found in South Sea and the most volume of oil spilt was shown in West Sea of Korea for 10 years.

• Journal of the Korean Society of Food Science and Nutrition
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• v.45 no.11
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• pp.1673-1680
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• 2016

The purpose of this study was to examine how customer orientation (CO) reduces employee stress to customers (CSS). As emotional labor strategies [surface acting (SA) and deep acting (DA)] may mediate a role between CO and CSS, we verified multiple parallel mediator roles of SA and DA between CO and CSS. Our survey was administered to 323 school foodservice employees in Daegu and Gyeongbuk. The results show that CO increased DA but did not decrease SA, and SA had a positive effect on CSS while DA did not influence CSS. These results did not support the parallel multiple mediator model. We conducted post-hoc model modification and proposed the serial multiple mediator model as a modified model. As a result, CO increased DA, DA reduced SA, and SA showed a positive relation with CSS. This double mediating effect through DA and SA between CO and CSS was significant. Based on these results, we found that CO did not have a direct effect on SA and CSS. DA did not directly reduce CSS while CO reduced SA and CSS through DA indirectly. DA had a negative effect on CSS through SA indirectly. Finally, implications and limitations of this are discussed.

• KIPS Transactions on Software and Data Engineering
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• v.4 no.11
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• pp.509-520
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• 2015

College Scholastic Ability Test(CSAT) is a primary test to evaluate the study achievement of high-school students and used by most universities for admission decision in South Korea. Because its level of difficulty is a significant issue to both students and universities, the government makes a huge effort to have a consistent difficulty level every year. However, the actual levels of difficulty have significantly fluctuated, which causes many problems with university admission. In this paper, we build two types of data-driven prediction models to predict correct answer rate and to identify significant factors for CSAT English test through accumulated test data of CSAT, unlike traditional methods depending on experts' judgments. Initially, we derive candidate question-specific factors that can influence the correct answer rate, such as the position, EBS-relation, readability, from the annual CSAT practices and CSAT for 10 years. In addition, we drive context-specific factors by employing topic modeling which identify the underlying topics over the text. Then, the correct answer rate is predicted by multiple linear regression and level of difficulty is predicted by classification tree. The experimental results show that 90% of accuracy can be achieved by the level of difficulty (difficult/easy) classification model, whereas the error rate for correct answer rate is below 16%. Points and problem category are found to be critical to predict the correct answer rate. In addition, the correct answer rate is also influenced by some of the topics discovered by topic modeling. Based on our study, it will be possible to predict the range of expected correct answer rate for both question-level and entire test-level, which will help CSAT examiners to control the level of difficulties.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.8 no.4
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• pp.357-368
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• 2003

Time-series CTDT (Conductivity/Temperature/Depth/Transmissivity) were obtained at one point near tidewater glacier of Marian Cove (King George Islands, Antarctica) to present water column properties and SPM (suspended particulate matter) dispersal pattern in relation with tide, current, meteorological data, and SPM concentration. Four layers were divided from the water column characteristics measured in the interval of an hour for about 2 days: 1) cold, fresh, and turbid surface mixed layer between 0-20 m in water depth, 2) warm, saline, and relatively clean Maxwell Bay inflow between 20-40 m in water depth, 3) turbid/cold tongue of subglacial discharges compared with the ambient waters between 40-70 m in water depth, and 4) cold, saline, and clean bottom water beneath 70 m in water depth. Surface plume, turbid freshwater at coastal/cliff area in late summer (early February), had the characteristic temperature and SPM concentration according to morphology, glacial condition, and composition of sediments. The restrict dispersion only over the input source of meltwater discharges was due to calm wether condition. Due to strong wind-induced surface turbulence, fresh and turbid surface plume, englacial upwelling cold water, glacier-contact meltwater, and Maxwell Bay inflow was mixing at ice-proximal zone and the consequent mixed layer deepened at the surface. Large amount of precipitation, the major controlling factor for increasing short-term glacial discharges, was accompanied by the apparent development of subglacial discharge that resulted in the rapid drop of salinity below the mid depth. Although amount of subglacial discharge and englacial upwelling may be large, however, their low SPM concentration would have small influence on bottom deposition of terrigenous sediments.