• Title/Summary/Keyword: Product Techniques

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The Prediction of DEA based Efficiency Rating for Venture Business Using Multi-class SVM (다분류 SVM을 이용한 DEA기반 벤처기업 효율성등급 예측모형)

  • Park, Ji-Young;Hong, Tae-Ho
    • Asia pacific journal of information systems
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    • v.19 no.2
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    • pp.139-155
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    • 2009
  • For the last few decades, many studies have tried to explore and unveil venture companies' success factors and unique features in order to identify the sources of such companies' competitive advantages over their rivals. Such venture companies have shown tendency to give high returns for investors generally making the best use of information technology. For this reason, many venture companies are keen on attracting avid investors' attention. Investors generally make their investment decisions by carefully examining the evaluation criteria of the alternatives. To them, credit rating information provided by international rating agencies, such as Standard and Poor's, Moody's and Fitch is crucial source as to such pivotal concerns as companies stability, growth, and risk status. But these types of information are generated only for the companies issuing corporate bonds, not venture companies. Therefore, this study proposes a method for evaluating venture businesses by presenting our recent empirical results using financial data of Korean venture companies listed on KOSDAQ in Korea exchange. In addition, this paper used multi-class SVM for the prediction of DEA-based efficiency rating for venture businesses, which was derived from our proposed method. Our approach sheds light on ways to locate efficient companies generating high level of profits. Above all, in determining effective ways to evaluate a venture firm's efficiency, it is important to understand the major contributing factors of such efficiency. Therefore, this paper is constructed on the basis of following two ideas to classify which companies are more efficient venture companies: i) making DEA based multi-class rating for sample companies and ii) developing multi-class SVM-based efficiency prediction model for classifying all companies. First, the Data Envelopment Analysis(DEA) is a non-parametric multiple input-output efficiency technique that measures the relative efficiency of decision making units(DMUs) using a linear programming based model. It is non-parametric because it requires no assumption on the shape or parameters of the underlying production function. DEA has been already widely applied for evaluating the relative efficiency of DMUs. Recently, a number of DEA based studies have evaluated the efficiency of various types of companies, such as internet companies and venture companies. It has been also applied to corporate credit ratings. In this study we utilized DEA for sorting venture companies by efficiency based ratings. The Support Vector Machine(SVM), on the other hand, is a popular technique for solving data classification problems. In this paper, we employed SVM to classify the efficiency ratings in IT venture companies according to the results of DEA. The SVM method was first developed by Vapnik (1995). As one of many machine learning techniques, SVM is based on a statistical theory. Thus far, the method has shown good performances especially in generalizing capacity in classification tasks, resulting in numerous applications in many areas of business, SVM is basically the algorithm that finds the maximum margin hyperplane, which is the maximum separation between classes. According to this method, support vectors are the closest to the maximum margin hyperplane. If it is impossible to classify, we can use the kernel function. In the case of nonlinear class boundaries, we can transform the inputs into a high-dimensional feature space, This is the original input space and is mapped into a high-dimensional dot-product space. Many studies applied SVM to the prediction of bankruptcy, the forecast a financial time series, and the problem of estimating credit rating, In this study we employed SVM for developing data mining-based efficiency prediction model. We used the Gaussian radial function as a kernel function of SVM. In multi-class SVM, we adopted one-against-one approach between binary classification method and two all-together methods, proposed by Weston and Watkins(1999) and Crammer and Singer(2000), respectively. In this research, we used corporate information of 154 companies listed on KOSDAQ market in Korea exchange. We obtained companies' financial information of 2005 from the KIS(Korea Information Service, Inc.). Using this data, we made multi-class rating with DEA efficiency and built multi-class prediction model based data mining. Among three manners of multi-classification, the hit ratio of the Weston and Watkins method is the best in the test data set. In multi classification problems as efficiency ratings of venture business, it is very useful for investors to know the class with errors, one class difference, when it is difficult to find out the accurate class in the actual market. So we presented accuracy results within 1-class errors, and the Weston and Watkins method showed 85.7% accuracy in our test samples. We conclude that the DEA based multi-class approach in venture business generates more information than the binary classification problem, notwithstanding its efficiency level. We believe this model can help investors in decision making as it provides a reliably tool to evaluate venture companies in the financial domain. For the future research, we perceive the need to enhance such areas as the variable selection process, the parameter selection of kernel function, the generalization, and the sample size of multi-class.

Corrosion Characteristics of Excavated Bronze Artifacts According to Corrosion Environment (부식 환경에 따른 출토 청동 유물의 부식 특성)

  • Jang, Junhyuk;Bae, Gowoon;Chung, Kwangyong
    • Korean Journal of Heritage: History & Science
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    • v.53 no.1
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    • pp.24-33
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    • 2020
  • In excavated bronze artifacts, corrosion products of various shapes and colors are observed due to multiple corrosion factors coexisting in the burial environment, and these corrosion products can constitute important data not only in terms of long-term corrosion-related information, but also in connection with preservation of artifacts. As such, scientific analysis is being carried out on the corrosion layer and corrosion products of bronze artifacts, and the corrosion mechanism and the characteristics of corrosion products elucidated, which is essential for interpreting the exposed burial environment and its association with corrosion factors inside the burial environment. In this study, after classifying excavated bronze artifacts according to alloy ratio and fabrication technique, comprehensive analysis of the surface of corrosion artifacts, corrosion layer, and corrosion products was carried out to investigate the corrosion mechanism, formation process of the corrosion layer, and characteristics of corrosion products. The study designated two groups according to alloy ratio and fabrication technique. In Group 1, which involved a Cu-Sn-Pb alloy and had no heat treatment, the surface was rough and external corrosion layers were formed on a part, or both sides, of the inside and the outside, and the surface was observed as being green or blue. α+δ phase selection corrosion was found in the metal and some were found to be concentrated in an empty space with a purity of 95 percent or more after α+δ phase corrosion. The Cu-Sn alloy and heat-treated Group 2 formed a smooth surface with no external corrosion layer, and a dark yellow surface was observed. In addition, no external corrosion layer was observed, unlike Group 1, and α corrosion was found inside the metal. In conclusion, it can be seen that the bronze artifacts excavated from the same site differ in various aspects, including the formation of the corrosion layer, the shape and color of the corrosion products, and the metal ion migration path, depending on the alloy ratio and fabrication technique. They also exhibited different corrosion characteristics in the same material, which means that different forms of corrosion can occur depending on the exposure environment in the burial setting. Therefore, even bronze artifacts excavated from the same site will have different corrosion characteristics depending on alloy ratio, fabrication technique, and exposure environment. The study shows one aspect of corrosion characteristics in specific areas and objects; further study of corrosion mechanisms in accordance with burial conditions will be required through analysis of the corrosive layer and corrosive product characteristics of bronze artifacts from various regions.

A Study on the Telemetry System for the Inhabitant Environment and Distribution of Fish-III -Oxygen, pH, Turbidity and Distribution of Fishes- (어류의 서식환경과 분포생태의 원격계측에 관한 연구 -III -$용존산\cdot$pH 및 독도와 어류의 분포생태-)

  • 신형일;안영화;신현옥
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.35 no.2
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    • pp.136-146
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    • 1999
  • The telemetry system for the oxygen, pH, turbidity and the distribution ecology of fishes was constructed by the authors in order to product and manage effectively in shallow sea culture and setnets fisheries, and then the experiments for the telemetry system carried out at the culturing fishing ground in coast of Sanyang-Myon, Kyoungsangnam-Do and the set net fishing ground located Nungpo bay in Kojedo province respectively from October, 1997 to June 1998.As those results, the techniques suggested in the telemetry system for which find out the relationship between the physical and chemical environment in the sea and the distribution ecology of fishes gave full display its function, and its system could be operated as real time system. This research can also provide base-line data to develope a hybrid system unifying the marine environment information and the fisheries resources information in order to manage effectively coastal fishing ground.

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Introduced Plant Pathogenes and Plant Quarantine in Korea (침입병원균(侵入病原菌)과 식물검역(植物檢疫))

  • Park, Jong-Seong
    • Korean Journal of Agricultural Science
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    • v.3 no.1
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    • pp.121-134
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    • 1976
  • There are many evidences that vaiious plant pathogenes were introduced with imported plants and agricultural productsrfrom foreign countries and caused heavy losses of domestic economic plants, ever since the early twentieth century when our country began to trade plants and agricultural products with foreign countries. There are many ways that foreign plant pathogenes have been introduced into our country, but the main route is considered to be imported plants and agricultural products contaminated with plant pathogenes. Plant quarantine which prevent effectively introduction of plant pathogenes from abroad was practiced for the first time in our country in 1912, and that is relatively earlier activity in the history of plant quarantine of the world. Several plant pathogenes have been introduced into our country even after plant quarantine had been practiced. Particularly for about 15 years, from the 2nd World War to 1961 when the law of Plant Protection was enacted and practical works of plant quarantine was reoperated, Korean agriculture was opened to various foreign plant pathogenes as a lapse period of plant quarantine in our country. Introduced plant pathogenes are, for the most part, from Japan because of depending upon Japan in the foreign trade of plants and agricultural products of our country. As present plant quarantine is required more exactness and rapidness, reasonable organization of quarantine system including more trained quarantine specialists, modernized facilities and introduction of improved quarantine techniques are necessary. Reasonable organization and improvement of plant quarantine system are important not only for protection of korean agriculture to plant pathogenes possible to be introduced from foreing countries, but also for increasing and stabilization of export of plants and agricultural product of our country.

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Comparison of Cardioprotection between Histidine-Tryptophan-Ketoglutarate Cardioplegia and DelNido Cardioplegia in Isolated Rat Hearts (흰쥐의 적출심장에서 HTK 심정지액과 DelNido 심정지액의 심근보호효과비교)

  • 공준혁;김대현;장봉현
    • Journal of Chest Surgery
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    • v.36 no.11
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    • pp.799-811
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    • 2003
  • Background: The aim of this study is to define the cardioprotective effects (hemodynamic, cytochemical and ultrastructural of the newly developed Histidine-Tryptophan-Ketoglutarate (HTK) cardioplegia compared to DelNido cardioplegia. Material and Method: Seventy-nine isolated rat hearts were divided into three groups on the basis of techniques of cardioplegia infusion. Twenty-eight hearts (Group 1) were flushed with cold DelNido cardioplegia with every 40 minutes for 2 hours. Twenty-seven hearts (Group 2) were flushed with cold HTK cardioplegia for once during the 2 hours. Twenty-four hearts (Group 3) were flushed with cold HTK cardioplegia with every 40 minutes for 2 hours. Heart rate, left ventricular developed pressure (LVDP), changes of + dp/dt max, coronary flow, and rate-pressure product value were measured at pre-ischemic, post-reperfusion 15 minutes, 30 minutes, and 45 minutes for hemodynamic study. Aspartate aminotransferase (AST), lactate dehydrogenase (LD), creatine kinase (CK), CK-MB, troponin-I, myoglobin, and lactate were measured at pre-ischemic and post-reperfusion 45 minutes for cytochemical parameters. Mitochondrial scores were counted in 3 cases from each group for ultrastructural assessment. Result: In hemodynamic study, there were no significant differences among group 1, group 2, and group 3. However, the decrease values of heart rate in group 2 and 3 exhibited significantly lower values than in group 1. In cytochemical study, there were no significant differences among group 1, group 2, and group 3. However, the increase values of lactate in group 2 and 3 exhibited significantly lower values than in group 1. In ultrastructural assessment, the mean myocardial mitochondria scores in group 1, group 2, and group 3 were 2.14$\pm$0.10, 1.52$\pm$0.57, and 2.10$\pm$0.16. Conclusion: HTK solution provides adequate myocardial protection with some advantages over DelNido solution in isolated rat hearts.

Environmental Leachability of Electric Arc Furnace Dust for Applying as Hazardous Material Treatment (제강분진을 이용한 유해물질 처리기술 적용을 위한 안전성 평가)

  • Lee, Sang-Hoon;Kang, Sung-Ho;Kim, Jee-Hoon;Chang, Yoon-Seok
    • Journal of Korean Society of Environmental Engineers
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    • v.28 no.3
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    • pp.329-336
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    • 2006
  • Iron manufacturing process involves production of various by-product including slag, sludge, sintering and EAF(Electric Arc furnace dust). Some of the by-products such as EAF and sintering dust are disposed of as waste due to their high heavy metal contents. It has been notice for many years that the EAF dust also contain about 65% of Fe(0) and Fe(II) and then the possible utilization of the iron. One possibility is to apply the EAF as a lining material in conjunction with clay or HDPE liners, in waste landfill. The probable reaction between the leachate containing toxic elements such as TCE, PCE dioxine and $Cr^{6+}$ is reduction of the toxic materials in corresponding to the oxidation of the reduced iron and therefore diminishing the toxicity of the leachate. It is, however, prerequisite to evaluate the leaching characteristics of the EAF dust before application. Amelioration of the leachate would be archived only when the level of toxic elements in the treated leachate is less than that of in the untreated leachate. Several leaching techniques were selected to cover different conditions and variable environments including time, pH and contact method. The testing methods include availability test, pH-stat test and continuous column test. Cr and Zn are potentially leachable elements among the trace metals. The pH of the EAF dust is highly alkaline, recording around 12 and Zn is unlikely to be leached under the condition. On the contrary Cr is more leachable under alkaline environment. However, the released Cr should be reduced to $Cr^{3+}$ and then removed as $Cr(OH)_3$. Removal of the Cr is observed in the column test and further study on the specific reaction of Cr and EAF dust is underway.

A Study on the Brand Characteristics According to Trends in the Children's Apparel Market

  • Han, Gyung-Hee
    • Journal of Fashion Business
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    • v.9 no.6
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    • pp.160-174
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    • 2005
  • Despite the decrease in the number of children due to low birth rate, the domestic children's apparel market has been achieving steady growth as family income is rising thanks to more opportunities for working women, parents spend more on their children, and they prefer brand products that make their children look special. In addition, the market is suffering from hard competition as large enterprises have joined the race. The present study purposed to survey the children's apparel market in Korea, which is in a transitional period, and to contribute to the development of the market with Korean brands. For this purpose, we analyzed the characteristics of children's apparel brands in the 21st century based on the current state of the domestic children's apparel market and, based on the findings, forecasted the future trend of children's apparel brands, suggested improvements for expected problems, proposed standards for coping with changes such as diversification, high quality and differentiation in the children's apparel market, and provided consumers with information on how to purchase products. According to the result of analyzing the characteristics of children's apparel brands in the 21st century, brands are categorized largely into four types - life cultural brands, functional product brands, character brands and brands advancing to China. Life cultural brands equipped with all necessities for children are expanding, and with the deepening social problems of environmental pollution and the reduction of the child population, functional products made of environment-friendly materials are spreading widely, targeting infants and children. Furthermore, for extending age targets and diversifying products, children's apparel is using characters. The use of characters is expected to have a considerable effect on the growth of brands because children are more subjective as consumers than before and they are more easily persuaded with characters. Domestic children's apparel brands advancing to China have a high expectation of success in overcoming the limitation of the local market that has reached its peak and growing into global brands. Korean apparel makers are struggling to overcome the depressed domestic market, to recover consumers' consumption, to cope with market opening, to pursue high value of sensibility and to expand the seniors' market, etc. In this situation, future trends of children's apparel brands will be the expansion of family brands, brand totalization, quality price, niche market (pre-teen market), etc. In response to these trends, we made the following suggestions for improvement. 1. Children's apparel brands are evolving into family brands as well as into total brands through voluming. Today, however, apparel makers are advancing to the children's apparel market with the concept of adults' apparel and, as a result, children's apparel is merely adults' apparel of reduced size, having problems in design, color and materials. Thus, apparel makers must develop design considering the wide range of size and the characteristics of children's apparel, strengthen sourcing abilities to create revenues, and make thorough survey of customers to find common denominators between adults' apparel and children's apparel considering that characteristic that the target class is different from the buyer class. Furthermore, they must make active investments in human resources, develop outstanding products through advanced planning and design, and support marketing techniques and management systems to stores. 2. As the declining birth rate will continue to have a negative effect on the market, it may be difficult to expand the market size but there is still a margin for growth through high-sensibility and high-quality products. The competitiveness of brands is determined by their market shares. Accordingly, concepts should be specialized according to lifestyle, customers' diverse needs should be satisfied, and cross-coordination should be achieved within a brand. 3. Considering Korean parents who do not spare investment in their children despite shrinking consumption, functional products must be high value-added goods that can enhance efficiency. However, in the current situation of the infants' apparel industry where a textile manufacturer supply its products to multiple brands, it is difficult to develop unique products only based on materials. Thus, it is considered urgent to appeal to consumers not by relying on materials only but by finding methods of applying their own characters to children's dress.

Two new triterpenoid saponins derived from the leaves of Panax ginseng and their antiinflammatory activity

  • Li, Fu;Cao, Yufeng;Luo, Yanyan;Liu, Tingwu;Yan, Guilong;Chen, Liang;Ji, Lilian;Wang, Lun;Chen, Bin;Yaseen, Aftab;Khan, Ashfaq A.;Zhang, Guolin;Jiang, Yunyao;Liu, Jianxun;Wang, Gongcheng;Wang, Ming-Kui;Hu, Weicheng
    • Journal of Ginseng Research
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    • v.43 no.4
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    • pp.600-605
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    • 2019
  • Background: The leaves and roots of Panax ginseng are rich in ginsenosides. However, the chemical compositions of the leaves and roots of P. ginseng differ, resulting in different medicinal functions. In recent years, the aerial parts of members of the Panax genus have received great attention from natural product chemists as producers of bioactive ginsenosides. The aim of this study was the isolation and structural elucidation of novel, minor ginsenosides in the leaves of P. ginseng and evaluation of their antiinflammatory activity in vitro. Methods: Various chromatographic techniques were applied to obtain pure individual compounds, and their structures were determined by nuclear magnetic resonance and high-resolution mass spectrometry, as well as chemical methods. The antiinflammatory effect of the new compounds was evaluated on lipopolysaccharide-stimulated RAW 264.7 cells. Results and conclusions: Two novel, minor triterpenoid saponins, ginsenoside $LS_1$ (1) and 5,6-didehydroginsenoside $Rg_3$ (2), were isolated from the leaves of P. ginseng. The isolated compounds 1 and 2 were assayed for their inhibitory effect on nitric oxide production in LPS-stimulated RAW 264.7 cells, and Compound 2 showed a significant inhibitory effect with $IC_{50}$ of $37.38{\mu}M$ compared with that of NG-monomethyl-L-arginine ($IC_{50}=90.76{\mu}M$). Moreover, Compound 2 significantly decreased secretion of cytokines such as prostaglandin $E_2$ and tumor necrosis factor-${\alpha}$. In addition, Compound 2 significantly suppressed protein expression of inducible nitric oxide synthase and cyclooxygenase-2. These results suggested that Compound 2 could be used as a valuable candidate for medicinal use or functional food, and the mechanism is warranted for further exploration.

Non-invasive Brain Stimulation and its Legal Regulation - Devices using Techniques of TMS and tDCS - (비침습적 뇌자극기술과 법적 규제 - TMS와 tDCS기술을 이용한 기기를 중심으로 -)

  • Choi, Min-Young
    • The Korean Society of Law and Medicine
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    • v.21 no.2
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    • pp.209-244
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    • 2020
  • TMS and tDCS are non-invasive devices that treat the diseases of patients or individual users, and manage or improve their health by applying stimulation to a brain through magnetism and electricity. The effect and safety of these devices have proved to be valid in several diseases, but research in this area is still much going on. Despite increasing cases of their application, legislations directly regulating TMS and tDCS are hard to find. Legal regulation regarding TMS and tDCS in the United States, Germany and Japan reveals that while TMS has been approved as a medical device with a moderate risk, tDCS has not yet earned approval as a medical device. However, the recent FDA guidance, European MDR changes, recalls in the US, and relevant legal provisions of Germany and Japan, as well as recommendations from expert groups all show signs of tDCS growing closer to getting approved as a medical device. Of course, safety and efficacy of tDCS can still be regulated as a general product instead of as a medical device. Considering multiple potential impacts on a human brain, however, the need for independent regulation is urgent. South Korea also lacks legal provisions explicitly regulating TMS and tDCS, but they fall into the category of the grade 3 medical devices according to the notifications of the Korean Ministry of Food and Drug Safety. And safety and efficacy of TMS are to be evaluated in compliance with the US FDA guidance. But no specific guidelines exist for tDCS yet. Given that tDCS devices are used in some hospitals in reality, and also at home by individual buyers, such a regulatory gap must quickly be addressed. In a longer term, legal system needs to be in place capable of independently regulating non-invasive brain stimulating devices.

Effects of Storytelling in Advertising on Consumers' Empathy

  • Park, Myungjin;Lee, Doo-Hee
    • Asia Marketing Journal
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    • v.15 no.4
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    • pp.103-129
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    • 2014
  • Differentiated positioning becomes increasingly difficult when brand salience weakens. Also, the daily increase in new media use and information load has led to a social climate that regards advertising stimuli as spamming. For these reasons, the focus of advertisement-related communication is shifting from persuading consumers through the direct delivery of information to an emphasis on appealing to their emotions using matching stimuli to enhance persuasion effects. Recently, both academia and industry have increasingly shown an interest in storytelling methods that can generate positive emotional responses and attitude changes by arousing consumers' narrative processing. The purpose of storytelling is to elicit consumers' emotional experience to meet the objectives of advertisement producers. Therefore, the most important requirement for storytelling in advertising is that it evokes consumers' sympathy for the main character in the advertisement. This does not involve advertisements directly persuading consumers, but rather, consumers themselves finding an answer through the advertisement's story. Thus, consumers have an indirect experience regarding the product features and usage through empathy with the advertisement's main character. In this study, we took the results of a precedent study as the starting point, according to which consumers' emotional response can be altered depending on the storytelling methods adopted for storytelling ads. Previous studies have reported that drama-type and vignette-type storytelling methods have a considerably different impact on the emotional responses of advertising audiences, due to their different structural characteristics. Thus, this study aims to verify that emotional response aroused by different types of advertisement storytelling (drama ads vs. vignette ads) can be controlled by the socio-psychological gender difference of advertising audiences and that the interaction effects between the socio-psychological gender differences of the audience and the gender stereotype of emotions to which advertisements appeal can exert an influence on emotional responses to types of storytelling in advertising. To achieve this, an experiment was conducted employing a between-group design consisting of 2 (storytelling type: drama ads vs. vignette ads) × 2 (socio-psychological gender of the audience: masculinity vs. femininity) × 2 (advertising appeal emotion type: male stereotype emotion vs. female stereotype emotion). The experiment revealed that the femininity group displayed a strong and consistent empathy for drama ads regardless of whether the ads appealed to masculine or feminine emotions, whereas the masculinity group displayed a stronger empathy for drama ads appealing to the emotional types matching its own gender as well as for vignette ads. The theoretical contribution of this study is significant in that it sheds light on the controllability of the audiences' emotional responses to advertisement storytelling depending on their socio-psychological gender and gender stereotype of emotions appealed to through advertising. Specifically, its considerable practical contribution consists in easing unnecessary creative constraints by comprehensively analyzing essential advertising strategic factors such as the target consumers' gender and the objective of the advertisement, in contrast to the oversimplified view of previous studies that considered emotional responses to storytelling ads were determined by the different types of production techniques used. This study revealed that emotional response to advertisement storytelling varies depending on the target gender of and emotion type appealed to by the advertisement. This suggests that an understanding of the targeted gender is necessary prior to producing an advertisement and that in deciding on an advertisement storytelling type, strategic attention should be directed to the advertisement's appeal concept or emotion type. Thus, it is safe to use drama-type storytelling that expresses masculine emotions (ex. fun, happy, encouraged) when the advertisement target, like Bacchus, includes both men and women. For brands and advertisements targeting only women (ex. female clothes), it is more effective to use a drama-type storytelling method that expresses feminine emotions (lovely, romantic, sad). The drama method can be still more effective than the vignette when women are the main target and a masculine concept-based creative is to be produced. However, when male consumers are targeted and the brand concept or advertisement concept is focused on feminine emotions (ex. romantic), vignette ads can more effectively induce empathy than drama ads.

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