• Title/Summary/Keyword: Numerical Characteristics

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Characteristics of Spectra of Daily Satellite Sea Surface Temperature Composites in the Seas around the Korean Peninsula (한반도 주변해역 일별 위성 해수면온도 합성장 스펙트럼 특성)

  • Woo, Hye-Jin;Park, Kyung-Ae;Lee, Joon-Soo
    • Journal of the Korean earth science society
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    • v.42 no.6
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    • pp.632-645
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    • 2021
  • Satellite sea surface temperature (SST) composites provide important data for numerical forecasting models and for research on global warming and climate change. In this study, six types of representative SST composite database were collected from 2007 to 2018 and the characteristics of spatial structures of SSTs were analyzed in seas around the Korean Peninsula. The SST composite data were compared with time series of in-situ measurements from ocean meteorological buoys of the Korea Meteorological Administration by analyzing the maximum value of the errors and its occurrence time at each buoy station. High differences between the SST data and in-situ measurements were detected in the western coastal stations, in particular Deokjeokdo and Chilbaldo, with a dominant annual or semi-annual cycle. In Pohang buoy, a high SST difference was observed in the summer of 2013, when cold water appeared in the surface layer due to strong upwelling. As a result of spectrum analysis of the time series SST data, daily satellite SSTs showed similar spectral energy from in-situ measurements at periods longer than one month approximately. On the other hand, the difference of spectral energy between the satellite SSTs and in-situ temperature tended to magnify as the temporal frequency increased. This suggests a possibility that satellite SST composite data may not adequately express the temporal variability of SST in the near-coastal area. The fronts from satellite SST images revealed the differences among the SST databases in terms of spatial structure and magnitude of the oceanic fronts. The spatial scale expressed by the SST composite field was investigated through spatial spectral analysis. As a result, the high-resolution SST composite images expressed the spatial structures of mesoscale ocean phenomena better than other low-resolution SST images. Therefore, in order to express the actual mesoscale ocean phenomenon in more detail, it is necessary to develop more advanced techniques for producing the SST composites.

Numerical Study on the Effect of the Arrangement Type of Rotor Sail on Lift Formation (로터세일의 배열 형태가 양력 형성에 미치는 영향에 관한 수치해석적 연구)

  • Jung-Eun Kim;Dae-Hwan Cho;Chang-Yong Lee
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.29 no.2
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    • pp.197-206
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    • 2023
  • Recently, the international community, including the International Maritime Organization (IMO), has strengthened regulations on air pollution emissions of ships, and eco-friendly ships are actively being developed to reduce exhaust gas emissions. Among them, rotor sail (RS), a wind-assisted ship propulsion system, is attracting attention again. RS is a cylindrical device installed on the ship deck, that generates hydrodynamic lift using a magnus effect. This is a next generation eco-friendly auxiliary propulsion technology, and Enercon company, which developed RS-applied ships, announced that fuel savings of more than 30% are possible. In this study, optimal installation conditions such as RS spacing and arrangement type were selected when multiple RSs were installed on ships. AR=5.1, SR=1.0, and De/D was fixed at 2.0 according to the RS arrangement, and the wind direction was considered only for the unidirectional +y-axis. Regarding arrangement conditions, five conditions were set at 3D intervals in the +x-axis direction from 3D to 15D and five conditions in the +y-axis direction from 5D to 25D. CL, CD and aerodynamic efficiency (CL/CD) were compared according to the square(□) and diamond(◇) shape arrangements. Consequently, the effect of RS on the longitudinal distance was not significantly different. However, in the case of RS flow characteristics according to the transverse distance, the interaction effect of RS was the greatest when the two RSs almost matched the wind direction. In the case of the RS flow characteristics according to the arrangement, notably, when the wind blew in the forward (0°) direction, the diamond (◇) arrangement was least affected by the backward flow between RSs.

Analysis on dynamic numerical model of subsea railway tunnel considering various ground and seismic conditions (다양한 지반 및 지진하중 조건을 고려한 해저철도 터널의 동적 수치모델 분석)

  • Changwon Kwak;Jeongjun Park;Mintaek Yoo
    • Journal of Korean Tunnelling and Underground Space Association
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    • v.25 no.6
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    • pp.583-603
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    • 2023
  • Recently, the advancement of mechanical tunnel boring machine (TBM) technology and the characteristics of subsea railway tunnels subjected to hydrostatic pressure have led to the widespread application of shield TBM methods in the design and construction of subsea railway tunnels. Subsea railway tunnels are exposed in a constant pore water pressure and are influenced by the amplification of seismic waves during earthquake. In particular, seismic loads acting on subsea railway tunnels under various ground conditions such as soft ground, soft soil-rock composite ground, and fractured zones can cause significant changes in tunnel displacement and stress, thereby affecting tunnel safety. Additionally, the dynamic response of the ground and tunnel varies based on seismic load parameters such as frequency characteristics, seismic waveform, and peak acceleration, adding complexity to the behavior of the ground-tunnel structure system. In this study, a finite difference method is employed to model the entire ground-tunnel structure system, considering hydrostatic pressure, for the investigation of dynamic behavior of subsea railway tunnel during earthquake. Since the key factors influencing the dynamic behavior during seismic events are ground conditions and seismic waves, six analysis cases are established based on virtual ground conditions: Case-1 with weathered soil, Case-2 with hard rock, Case-3 with a composite ground of soil and hard rock in the tunnel longitudinal direction, Case-4 with the tunnel passing through a narrow fault zone, Case-5 with a composite ground of soft soil and hard rock in the tunnel longitudinal direction, and Case-6 with the tunnel passing through a wide fractured zone. As a result, horizontal displacements due to earthquakes tend to increase with an increase in ground stiffness, however, the displacements tend to be restrained due to the confining effects of the ground and the rigid shield segments. On the contrary, peak compressive stress of segment significantly increases with weaker ground stiffness and the effects of displacement restrain contribute the increase of peak compressive stress of segment.

CLINICAL AND NEUROPSYCHOLOGICAL CHARACTERISTICS OF DSM-IV SUBTYPES OF ATTENTION DEFICIT HYPERACTIVITY DISORDER (주의력결핍 과잉행동장애의 아형별 신경심리학적 특성 비교)

  • Cheung, Seung-Deuk;Lee, Jong-Bum;Kim, Jin-Sung;Seo, Wan-Seok;Bai, Dai-Seg;Chun, Eun-Jin;Suh, Hae-Sook
    • Journal of the Korean Academy of Child and Adolescent Psychiatry
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    • v.13 no.1
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    • pp.139-152
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    • 2002
  • Objectives:This study was conducted to compare the clinical and neuropsychological characteristics by DSM-IV subtypes of attention deficit hyperactivity disorder(ADHD) patients who did not have comorbid psychiatric disorders. Methods:5-15 year old children with ADHD were recruited at psychiatric outpatient clinic of Yeungnam University hospital and the patients with comorbidity or neurological abnormalities were excluded. Finally, total 404 children with ADHD were selected for this study. There were 234 subjects of ADHD-C(57.9%), 156 subjects of ADHD-I(38.6%) and 14 subjects of ADHD-HI(3.5%), who fulfilled the DSM-IV diagnostic criteria. The mean age of the total subjects was 9.63±2.49 years old. The psychopathology, IQ, behavioral problems, neuropsychological executive function were evaluated before pharmacological treatment. The measures were Korean Personality Inventory of Child(K-PIC) for psychopathology, 4 behavioral check lists(ADDES-HV, ACTeRS, CAP, SNAP) for behavioral symptoms of ADHD, K-ABC and KEDI-WISC for IQ and Conner's CPT, WCST, SST for neuropsychological executive functions. Results:1) The prevalence of subtypes was ADHD-C, ADHD-I, ADHD-HI in decreasing order. There was no sex difference of prevalence among three subtypes. The mean age of ADHD-I was older than other subtypes. 2) There was significant differences of psychopathology among subtypes, the ADHD-C and ADHD-HI had higher than the ADHD-I in the scores of delinquent, hyperactivity and psychosis;the ADHD-C had higher than the ADHD-I in the scores of family relation and autism, the scores of ego resilience were lower than the ADHD-I. However, there was no difference in anxiety, depression and somatization scores among them. 3) The results of behavioral symptom check lists, the ADHD-C had higher the score of inattention, hyperactivity and impulsivity than the ADHD-I. Meanwhile the results of ACTeRs, which rated by the teachers, were different. 4) There were significant differences of sequential processing scale and arithmetics among subtypes in IQ using K-ABC, but there was no significant difference between the ADHD-C and the ADHD-I after excluding the ADHD-HI due to small numbers. 5) There was numerical difference among subtypes but did not reach statistical significance in three neuropsychological executive function tests. Conclusion:In conclusion, our results revealed that there was significant difference in clinical features among three subtypes but, no significant difference in executive functions.

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Growth Efficiency, Carcass Quality Characteristics and Profitability of 'High'-Market Weight Pigs ('고체중' 출하돈의 성장효율, 도체 품질 특성 및 수익성)

  • Park, M.J.;Ha, D.M.;Shin, H.W.;Lee, S.H.;Kim, W.K.;Ha, S.H.;Yang, H.S.;Jeong, J.Y.;Joo, S.T.;Lee, C.Y.
    • Journal of Animal Science and Technology
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    • v.49 no.4
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    • pp.459-470
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    • 2007
  • Domestically, finishing pigs are marketed at 110 kg on an average. However, it is thought to be feasible to increase the market weight to 120kg or greater without decreasing the carcass quality, because most domestic pigs for pork production have descended from lean-type lineages. The present study was undertaken to investigate the growth efficiency and profitability of ‘high’-market wt pigs and the physicochemical characteristics and consumers' acceptability of the high-wt carcass. A total of 96 (Yorkshire × Landrace) × Duroc-crossbred gilts and barrows were fed a finisher diet ad laibtum in 16 pens beginning from 90-kg BW, after which the animals were slaughtered at 110kg (control) or ‘high’ market wt (135 and 125kg in gilts & barrows, respectively) and their carcasses were analyzed. Average daily gain and gain:feed did not differ between the two sex or market wt groups, whereas average daily feed intake was greater in the barrow and high market wt groups than in the gilt and 110-kg market wt groups, respectively(P<0.01). Backfat thickness of the high-market wt gilts and barrows corrected for 135 and 125-kg live wt, which were 23.7 and 22.5 mm, respectively, were greater (P<0.01) than their corresponding 110-kg counterparts(19.7 & 21.1 mm). Percentages of the trimmed primal cuts per total trimmed lean (w/w), except for that of loin, differed statistically (P<0.05) between two sex or market wt groups, but their numerical differences were rather small. Crude protein content of the loin was greater in the high vs. 110-kg market group (P<0.01), but crude fat and moisture contents and other physicochemical characteristics including the color of this primal cut were not different between the two sexes or market weights. Aroma, marbling and overall acceptability scores were greater in the high vs. 110-kg market wt group in sensory evaluation for fresh loin (P<0.01); however, overall acceptabilities for cooked loin, belly and ham were not different between the two market wt groups. Marginal profits of the 135- and 125-kg high-market wt gilt and barrow relative to their corresponding 110-kg ones were approximately -35,000 and 3,500 wons per head under the current carcass grading standard and price. However, if it had not been for the upper wt limits for the A- and B-grade carcasses, marginal profits of the high market wt gilt and barrow would have amounted to 22,000 and 11,000 wons per head, respectively. In summary, 120~125-kg market pigs are likely to meet the consumers' preference better than the 110-kg ones and also bring a profit equal to or slightly greater than that of the latter even under the current carcass grading standard. Moreover, if only the upper wt limits of the A- & B-grade carcasses were removed or increased to accommodate the high-wt carcass, the optimum market weights for the gilt and barrow would fall upon their target weights of the present study, i.e. 135 and 125 kg, respectively.

The Characteristics and the Effects of Pollutant Loadings from Nonpoint Sources on Water Quality in Suyeong Bay (수영만 수질에 미치는 비점원 오염부하의 특성과 영향)

  • CHO Eun Il;LEE Suk Mo;PARK Chung-Kil
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.28 no.3
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    • pp.279-293
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    • 1995
  • The most obvious and easily recognizable sources of potential water pollution are point sources such as domestic and industrial wastes. But recently, the potential effects of nonpoint sources on water quality have been increased apparently. In order to evaluate the characteristics and the effects of nonpoint sources on water quality, this study was performed in Suyeong Bay from May, 1992 to July, 1992. The depth-averaged 2-dimensional numerical model, which consists of the hydrodynamic model and the diffusion model was applied to simulate the water quality in Suyeong Bay. When flowrate was $65.736m^3/s,$ the concentration of pollutants (COD, TSS and VSS) at Oncheon stream (Sebeong bridge) during second flush were very high as much as 121.4mg/l of COD, 1148.0mg/l of TSS and 262.0mg/1 of VSS. When flowrate was 4.686m^3/s, the concentration of pollutants $(TIN,\;NH_4\;^+-\;N,\;NO_2\;^--N\;and\;PO_4\;^{3-}-P)$ during the first flush were very high as much as 20.306mg/1 of TIN, 14.154mg/1 of $NH_4\;^+-N$, 9.571mg/l of $NO_2\;^--N$ and l.785mg/l of $PO_2\;^{3-}-P$ As results of the hydrodynamic model simulation, the computed maximum velocity of tidal currents in Suyeong Bay was 0.3m/s and their direction was clockwise flow for ebb tide and counter clockwise flow for Hood tide. Four different methods were applied for the diffusion simulation in Suyeong Bay. There were the effects for the water quality due to point loads, annual nonpoint loads and nonpoint loads during the wet weather and the investigation period, respectively. The efforts of annual nonpoint loads and nonpoint loads during the wet weather seem to be slightly deteriorated in comparison with the effects of point loads. However, the bay was significantly polluted by the nonpoint loads during the investigation period. In this case, COD and SS concentrations ranged 2.0-30.0mg/l, 7.0- 200.0mg/l in ebb tide, respectively. From these results, it can be emphasized that the large amount of pollutants caused by nonpoint sources during the wet weather were discharged into the bay, and affected significantly to both the water quality and the marine ecosystem. Therefore, it is necessary to consider the loadings of nonpoint pollutants to plan wastewater treatment plant.

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Effects of Supplemental Medicinal Plants (Artemisia, Acanthopanax and Garlic) on Productive Performance of Sows and on Growth and Carcass Traits in Finishing Pigs (약용식물(Artemisia, Acanthopanax and Garlic)의 급여가 돼지의 생산성에 미치는 영향)

  • Jang, Hae-Dong;Lee, Je-Hyun;Hong, Seong-Min;Jung, Ji-Hong;Kim, In-Ho
    • Journal of Animal Science and Technology
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    • v.52 no.2
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    • pp.103-110
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    • 2010
  • This study was conducted to determine the effect of supplemental medicinal plants (Artemisia, Acanthopanx and Garlic) on productive parameters in pigs. In experiment 1, a total of 90 multiparous sows were used in a 21-d performance study. The diets included: 1) CON (basal diet; Control), 2) BM1 (CON + 0.1% medicinal plants) and 3) BM2 (CON + 0.2% medicinal plants). Backfat thickness from farrowing to weaning was higher (P<0.05) in CON compared with sows fed treatments diets. The piglets weight gain was higher in the medicinal plants treatments (P<0.05). ADFI, nutrient digestibility and survivability were not affected by the experimental treatments. In experiment 2, a total of 60 finishing pigs (Landrace ${\times}$ Yorkshire ${\times}$ Duroc, $65.21\;{\pm}\;0.04\;kg$ average initial body weight) were used in a 56-d performance assay to determine the effects of supplemental medicinal plants (Artemisia, Acanthopanx and Garlic) on growth performance and carcass characteristics in finishing pigs. The dietary treatments included: 1) CON (basal diet ; Control), 2) BM1 (CON + 0.1% medicinal plants) and 3) BM2 (CON + 0.2% medicinal plants). For 4~8 weeks and overall period, ADG was higher (P<0.05) in the pigs fed medicinal plants. CON treatment was higher 24 pH loin and cooking loss than BM1 treatment (P<0.05). Water holding capacity and drip loss after 1day were affected by the dietary treatments (P<0.05). No numerical differences were observed in sensory evaluation, meat color, TBARS and loin area among three treatments. In conclusion, the results obtained from this feeding trial suggest that the medicinal plants mixture supplementation in diets for finishing pigs can improve ADG, water holding capacity, cooking loss and it improved backfat loss in sow and, litter weight gain.

Wintertime Extreme Storm Waves in the East Sea: Estimation of Extreme Storm Waves and Wave-Structure Interaction Study in the Fushiki Port, Toyama Bay (동해의 동계 극한 폭풍파랑: 토야마만 후시키항의 극한 폭풍파랑 추산 및 파랑 · 구조물 상호작용 연구)

  • Lee, Han Soo;Komaguchi, Tomoaki;Yamamoto, Atsushi;Hara, Masanori
    • Journal of Korean Society of Coastal and Ocean Engineers
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    • v.25 no.5
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    • pp.335-347
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    • 2013
  • In February 2008, high storm waves due to a developed atmospheric low pressure system propagating from the west off Hokkaido, Japan, to the south and southwest throughout the East Sea (ES) caused extensive damages along the central coast of Japan and along the east coast of Korea. This study consists of two parts. In the first part, we estimate extreme storm wave characteristics in the Toyama Bay where heavy coastal damages occurred, using a non-hydrostatic meteorological model and a spectral wave model by considering the extreme conditions for two factors for wind wave growth, such as wind intensity and duration. The estimated extreme significant wave height and corresponding wave period were 6.78 m and 18.28 sec, respectively, at the Fushiki Toyama. In the second part, we perform numerical experiments on wave-structure interaction in the Fushiki Port, Toyama Bay, where the long North-Breakwater was heavily damaged by the storm waves in February 2008. The experiments are conducted using a non-linear shallow-water equation model with adaptive mesh refinement (AMR) and wet-dry scheme. The estimated extreme storm waves of 6.78 m and 18.28 sec are used for incident wave profile. The results show that the Fushiki Port would be overtopped and flooded by extreme storm waves if the North-Breakwater does not function properly after being damaged. Also the storm waves would overtop seawalls and sidewalls of the Manyou Pier behind the North-Breakwater. The results also depict that refined meshes by AMR method with wet-dry scheme applied capture the coastline and coastal structure well while keeping the computational load efficiently.

A Morphological and Anatomical Study on the Leaves of the Genus Acer in Korea (한국산(韓國産) 단풍나무속(屬)의 잎의 형태(形態) 및 해부학적(解剖學的) 연구(硏究))

  • Park, Kwang Woo;Kim, Sam Sik
    • Journal of Korean Society of Forest Science
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    • v.64 no.1
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    • pp.52-63
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    • 1984
  • This study was intended to identify 17 taxa. (5 varieties and 12 species) of the genus Acer in Korea on the basis of the shapes of stomata, the type of trichome on the different part of leaves, the shapes, arrangement and number of stele in cross section of petiole. The results obtained were summarized as follows; 11 The shape of guard cells of stomata in the genus Acer was anomcytical, and the size of the cells ranged from 10.25 to $21.00{\mu}$ in length and from 7.57 to $11.83{\mu}$ in width. 2) Eleven types of trichome on the leaf in the genus Acer were found; pilose, sericeous, velutinous, woolly, glabrate, puberulent, bladder hair, hispid, hirsute and uncinate. This characteristics also established a good criterion for identification of species. 3) The stele of petiole in the genus Acer was characterized by eustele and atactostele with polybranch, and the six groups of the shape of numerical change of stele; B>M=T, BM

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Relationship between Brand Personality and the Personality of Consumers, and its Application to Corporate Branding Strategy

  • Kim, Young-Ei;Lee, Jung-Wan;Lee, Yong-Ki
    • Journal of Global Scholars of Marketing Science
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    • v.18 no.3
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    • pp.27-57
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    • 2008
  • Many consumers enjoy the challenge of purchasing a brand that matches well with their own values and personalities (for example, Ko et al., 2008; Ko et al., 2006). Therefore, the personalities of consumers can impact on the final selection of a brand and its brand personality in two ways: first, the consumers may incline to purchase a brand or a product that reflects their own personalities; second, consumers tend to choose a company that has similar brand personalities to those brands that are being promoted. Therefore, the objectives of this study are following: 1. Is there any empirical relationship between a consumer's personality and the personality of a brand that he or she chooses? 2. Can a corporate brand be differentiated by the brand personality? In short, consumers are more likely to hold favorable attitudes towards those brands that match their own personality and will most probably purchase those brands matching well with their personality. For example, Matzler et al. (2006) found that extraversion and openness were positively related to hedonic product value; and that the personality traits directly (openness) and indirectly (extraversion, via hedonic value) influenced brand effects, which in turn droved attitudinal and purchase loyalty. Based on the above discussion, the following hypotheses are proposed: Hypothesis 1: the personality of a consumer is related to the brand personality of a product/corporate that he/she purchases. Kuksov (2007) and Wernerfelt (1990) argued that brands as a symbolic language allowed consumers to communicate their types to each other and postulated that consumers had a certain value of communicating their types to each other. Therefore, how brand meanings are established, and how a firm communicate with consumers about the meanings of the brand are interesting topics for research (for example, Escalas and Bettman, 2005; McCracken, 1989; Moon, 2007). Hence, the following hypothesis is proposed: Hypothesis 2: A corporate brand identity is differentiated by the brand personality. And there are significant differences among companies. A questionnaire was developed for collecting empirical measures of the Big-Five personality traits and brand personality variables. A survey was conducted to the online access panel members through the Internet during December 2007 in Korea. In total, 500 respondents completed the questionnaire, and considered as useable. Personality constructs were measured using the Five-factor Inventory (NEO-FFI) scale and a total of 30 items were actually utilized. Brand personality was measured using the five-dimension scale developed by Aaker (1997). A total of 17 items were actually utilized. The seven-point Likert-type scale was the format of responses, for example, from 1 indicating strongly disagreed to 7 for strongly agreed. The Analysis of Moment Structures (AMOS) was used for an empirical testing of the model, and the Maximum Likelihood Estimation (MLE) was applied to estimate numerical values for the components in the model. To diagnose the presence of distribution problems in the data and to gauge their effects on the parameter estimates, bootstapping method was used. The results of the hypothesis-1 test empirically show that there exit certain causality relationship between a consumer's personality and the brand personality of the consumer's choice. Thus, the consumer's personality has an impact on consumer's final selection of a brand that has a brand personality matches well with their own personalities. In other words, the consumers are inclined to purchase a brand that reflects their own personalities and tend to choose a company that has similar brand personalities to those of the brand being promoted. The results of this study further suggest that certain dimensions of the brand personality cause consumers to have preference to certain (corporate) brands. For example, the conscientiousness, neuroticism, and extraversion of the consumer personality have positively related to a selection of "ruggedness" characteristics of the brand personality. Consumers who possess that personality dimension seek for matching with certain brand personality dimensions. Results of the hypothesis-2 test show that the average "ruggedness" attributes of the brand personality differ significantly among Korean automobile manufacturers. However, the result of ANOVA also indicates that there are no significant differences in the mean values among manufacturers for the "sophistication," "excitement," "competence" and "sincerity" attributes of the corporate brand personality. The tight link between what a firm is and its corporate brand means that there is far less room for marketing communications than there is with products and brands. Consequently, successful corporate brand strategies must position the organization within the boundaries of what is acceptable, while at the same time differentiating the organization from its competitors.

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