• Title/Summary/Keyword: 매개 효과 연구

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Effects of Arginine Vasopressin(AVP) Infusion on the Patients with Catecholamine-dependent Septic Shock (카테콜아민계 승압제를 투여중인 패혈성 쇼크 환자에서 아르기닌 바소프레신(AVP)의 효과)

  • Sheen, Seung Soo;Lim, Seung Guan;Jo, Sook Kyoung;Song, Kyoung Eun;Lee, Hyoung No;Oh, Yoon Jung;Park, Kwang Joo;Hwang, Sung Chul
    • Tuberculosis and Respiratory Diseases
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    • v.55 no.5
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    • pp.506-515
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    • 2003
  • Background : A decreased level of serum arginine vasopressin(AVP) and an increased sensitivity to an exogenous AVP is expected in patients with septic shock who often require a high infusion rate of catecholamines. The goal of the study was to determine whether an exogenous AVP infusion to the patients with septic shock would achieve a significant decrement in infusion rate of catecholamine vasopressors while maintaining hemodynamic stability and adequate urine output. Method : Eight patients with septic shock who require a high infusion rate of norepinephrine had received a trial of 4-hour AVP infusion with simultaneous titration of norepinephrine. Hemodynamic parameters and urine output were monitored during the AVP infusion and the monitoring continued up to 4 hours after the AVP infusion had stopped. Results : Mean arterial pressure showed no significant changes during the study period(p=0.197). Norepinephrine infusion rate significantly decreased with concurrent AVP administration(p=0.001). However, beneficial effects had disappeared after the AVP infusion was stopped. In addition, hourly urine output showed no significant changes throughout the trials(p=0.093). Conclusion : Concurrent AVP infusion achieved the catecholamine vasopressor sparing effect in the septic shock patients, but there was no evidence of the improvement of renal function. Further study may be indicated to determine whether AVP infusion would provide an organ-protective effect to the septic shock patients.

Potential Roles of Hedgehog and Estrogen in Regulating the Progression of Fatty Liver Disease (지방간 진행 조절에 대한 헤지호그와 에스트로겐의 잠재적 역할)

  • Hyun, Jeong-Eun;Jung, Young-Mi
    • Journal of Life Science
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    • v.21 no.12
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    • pp.1795-1803
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    • 2011
  • Non-alcoholic fatty liver disease accompanies the rise in the prevalence of obesity, diabetes and the tendency toward high-fat dietary habits. Specifically, the higher prevalence of non-alcoholic fatty liver disease in men and postmenopausal women seems to be caused by the protective effects of estrogen against liver fibrosis, or lack thereof. There are no effective preventive therapies for liver diseases because the mechanisms underlying the progression of fatty liver diseases to chronic liver diseases and the protective effects of estrogen against fibrogenesis remain unclear. Recently, it has been reported that the hedgehog signaling pathway plays an important role in the progression of chronic liver diseases. Hedgehog, a morphogen regulating embryonic liver development, is expressed in injured livers but not in adult healthy livers. The level of hedgehog expression parallels the stages of liver diseases. Hedgehog induces myofibroblast activation and hepatic progenitor cell proliferation and leads to excessive liver fibrosis, whereas estrogen inhibits the activation of hepatic stellate cells to myofibroblasts and prevents liver fibrosis. Although the mechanism underlying the opposing actions of hedgehog and estrogen on liver fibrosis remain unclear, the suppressive effects of estrogen on the expression of osteopontin, a profibrogenic extracellular matrix protein and cytokine, and the inductive effects of hedgehog on osteopontin transcription suggest that estrogen and hedgehog are associated with liver fibrosis regulation. Therefore, further research on the estrogen-mediated regulatory mechanisms underlying the hedgehog-signaling pathway can identify the mechanism underlying liver fibrogenesis and contribute to developing therapies for preventing the progression of fibrosis to chronic liver diseases.

Elementary School Teachers' and Company Teachers' Recognitions of the Informal Science Education Activity: 'Korea Junior Engineering Achievement' Case (비정규 과학교육 활동에 대한 초등 현직 교사와 기업 교사의 인식: '주니어 공학기술 교실' 사례를 중심으로)

  • Choi Jaehyeok;Yoon Hye-Gyoung
    • Journal of Korean Elementary Science Education
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    • v.24 no.4
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    • pp.391-398
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    • 2005
  • Recent studies say that informal learning is influential to students as much as formal teaming. Nowadays we can see various informal teaming inside and outside of the country. In 2004, it was the first attempt in Korea that engineer had gone to the elementary school fur activity that included scientific experiment and engineering work with students. National Academy of Engineering of Korea (NAEK) progressed activity with companies and elementary schools for students' making sense of engineer and what they are doing. To do that, NAEK had developed the network that company could support its local school's science education circumstance by engineers' visiting program. In 2004, seventeen companies including both large and small ones took part in the program called' Korea Junior Engineering Achievement (KJEA)'. In this program, engineers played the role of teacher (we call them company teacher), elementary school teachers played the role of organizing classes as a mediator. Elementary school teachers and company teachers' recognition is very important to make students' activity meaningful. The aim of this study was to give implication for informal science education activity for which engineers visit their local school. We got the result by survey and interview of company teachers and elementary school teachers. This study's result shows that almost company teachers and school teachers were in favor of purpose of this informal science education activity and satisfied with their participation. But some company teachers were not satisfied with worksheets, materials provided and relationship between school and company). Elementary school teachers and company teachers, both of them believed students' program as the key factor of success of informal science education activity. To make informal science education grow, school administrator and teacher need to have a will to utilize the activities more actively.

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Inhibitory effects of persimmon (Diospyros kaki Thumb.) against diet-induced hypertriglyceridemia/hypercholesterolemia in rats (떫은감 (Diospyros kaki Thumb.)이 흰쥐의 식이성 이상지질혈증에 미치는 영향)

  • Ahn, Youngsook;Regu, Geberea manuel Meron;Oh, Eun Kyoung;Kwon, Oran
    • Journal of Nutrition and Health
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    • v.50 no.3
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    • pp.225-235
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    • 2017
  • Purpose: This study aimed to investigate the potential of freeze-dried persimmon powder (Diospyros kaki Thumb.) to protect against dyslipidemia induced by a high-fat/cholesterol diet (HFD) in a rat model. Methods: Fifty Wistar rats were randomly divided into five groups: normal control (NC), high-fat/cholesterol control (HC), tannin in HFD (HT, 1% of diet), immature persimmon in HFD (HI, 7% of diet), and mature persimmon in HFD (HM, 7% of diet). Tannin was used as a positive control. Biochemical, molecular, and histopathological changes were observed in the blood and liver. Results: We confirmed that a high fat/cholesterol diet successfully induced dyslipidemia, which was characterized by significantly altered lipid profiles in the plasma and liver. However, oxidized low-density lipoprotein levels, histopathological damage in the liver, and hepatic triglyceride levels were significantly reduced in all HT, HI, and HM groups compared to those in the HF group. In contrast, plasma apolipoprotein B level was significantly reduced only in the HT and HM groups, whereas reduction of the LDL-C level was detected only in the HI group. Although HF-induced sterol regulatory element-binding protein (SREBP) gene expression was significantly reduced in all treated groups, downstream gene expression levels varied among the different groups; significant reduction of fatty acid synthase (FAS) and 3-hydroxy-3-methylglutaryl-CoA (HMGCR) gene expression was detected only in the HI group, whereas cholesterol $7{\alpha}$-hydroxylase (CYP7A1) gene expression was significantly elevated only in the HM group. Conclusion: Taken together, the data suggest that protection of LDL oxidation and hepatic lipogenesis might be, at least partly, attributed to tannin in persimmons. However, the identified mechanisms varied up to the maturation stage of persimmon. In the case of immature persimmon, modulation of FAS and HMGCR gene expression was prominent, whereas in the case of mature persimmon, modulation of CYP7A1 gene expression was prominent.

Clinical Effects of an Improved Pump Reaction Rate and Automatic Occlusion Sensing System in Phacoemulsification (수정체유화장치의 초음파 출력속도 및 자동막힘감지 기능 향상의 술 후 임상결과 비교)

  • Kim, You Na;Lee, Jin Ah;Kim, Jae Yong;Kim, Myoung Joon;Tchah, Hung Won
    • Journal of The Korean Ophthalmological Society
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    • v.59 no.11
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    • pp.1017-1023
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    • 2018
  • Purpose: A recently introduced phacoemulsification system, the WhiteStar $Signature^{(R)}$ PRO, has demonstrated improved nucleus followability and cutting efficiency via an improved pump regulator with a higher reaction response and an automatic occlusion sensing system. In this study, we compared various phacoemulsification parameters between the new system and an older version of the device. Methods: A total of 80 eyes of 68 patients with cataracts who had undergone phacoemulsification by a single surgeon were included in this study. Forty eyes of patients underwent phacoemulsification using the older $Signature^{(R)}$ system (WhiteStar); these patients were classified as the control group. Another 40 eyes of patients underwent phacoemulsification with the newer enhanced system, the WhiteStar $Signature^{(R)}$ PRO; these patients were assigned to the experimental group. During the operation, operative parameters, including the effective phaco time (parameter of effective phaco time with a specific coefficient for the transversal movement expressed in seconds, EFX), ultrasound time (seconds [s]), effective phacoemulsification time (EPT, s), average phacoemulsification power (AVG, %), and balanced salt solution usage, were measured to determine the performance enhancement offered by the updated system. Central corneal thickness was measured before and after surgery to compare corneal edema. The relationships between the two groups were analyzed using an independent t-test. Results: The Signature $PRO^{(R)}$ system showed a lower EFX (p < 0.001), a shorter EPT (p < 0.001), and a smaller AVG (p < 0.001). Postoperative corneal thickness did not differ significantly between the two groups. Conclusions: Comparing the efficacy of the improved reaction speed of the device and automatic occlusion sensing system in performing phacoemulsification, the updated Signature $PRO^{(R)}$ system demonstrated superior followability and cutting efficiency regardless of nuclear cataract hardness.

Synthesis of Ultrasound Contrast Agent: Characteristics and Size Distribution Analysis (초음파 조영제의 합성 및 합성된 초음파 조영제의 특성 분석)

  • Lee, Hak Jong;Yoon, Tae Jong;Yoon, Young Il
    • Ultrasonography
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    • v.32 no.1
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    • pp.59-65
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    • 2013
  • Purpose: The purpose of this study is to establish the methodology regarding synthesis of ultrasound contrast agent imaging, and to evaluate the characteristics of the synthesized ultrasound contrast agents, including size or degradation interval and image quality. Materials and Methods: The ultrasound contrast agent, composed of liposome and SF6, was synthesized from the mixture solution of $21{\mu}mol$ DPPC (1, 2-Dihexadecanoyl-sn-glycero-3-phosphocholine, $C_{40}H_{80}NO_8P$), $9{\mu}mol$ cholesterol, $1.9{\mu}mol$ of DCP (Dihexadecylphosphate, $[CH_3(CH_2)_{15}O]_2P(O)OH$), and chloroform. After evaporation in a warm water bath and drying during a period of 12-24 hours, the contrast agent was synthesized by the sonication process by addition of buffer and SF6 gas. The size of the contrast agent was controlled by use of either extruder or sonication methods. After synthesis of contrast agents, analysis of the size distribution of the bubbles was performed using dynamic light scattering measurement methods. The degradation curve was also evaluated by changes in the number of contrast agents via light microscopy immediate, 12 hours, 24 hours, 36 hours, 48 hours, 60 hours, 72 hours, and 84 hours after synthesis. For evaluation of the role as an US contrast agent, the echogenicity of the synthesized microbubble was compared with commercially available microbubbles (SonoVue, Bracco, Milan, Italy) using a clinical ultrasound machine and phantom. Results: The contrast agents were synthesized successfully using an evaporation-drying-sonication method. The majority of bubbles showed a mean size of 154.2 nanometers, and they showed marked degradation 24 hours after synthesis. ANOVA test revealed a significant difference among SonoVue, synthesized contrast agent, and saline (p < 0.001). Although no significant difference was observed between SonoVue and the synthesized contrast agent, difference in echogenicity was observed between synthesized contrast agent and saline (p < 0.01). Conclusion: We could synthesize ultrasound contrast agents using an evaporation-drying-sonication method. On the basis of these results, many prospective types of research, such as anticancer drug delivery, gene delivery, including siRNA or microRNA, targeted molecular imaging, and targeted therapy can be performed.

A Study of the Anti-inflammatory Effect of Protein Derived from Tenebrio molitor Larvae (알칼리 법으로 추출한 갈색거저리 유충 단백질의 항염증 효능)

  • Seo, Minchul;Lee, Hwa Jeong;Lee, Joon Ha;Baek, Minhee;Kim, In-Woo;Kim, Sun Young;Hwang, Jae-Sam;Kim, Mi-Ae
    • Journal of Life Science
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    • v.29 no.8
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    • pp.854-860
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    • 2019
  • This study investigated the optimum pH conditions for efficient extraction of protein from defatted Tenebrio molitor (TM) larvae. We examined the anti-inflammatory effect of protein derived from defatted TM larvae obtained by an alkaline extraction method. Six extraction pH values (7, 8, 9, 10, 11, and 12) and three precipitation pH values (2, 4, and 6) were used. The protein content, browning degree, and recovery yield of the protein obtained under each pH condition were determined. For efficient extraction of protein from defatted TM larvae, a combination of an extraction pH of 9 and precipitation pH of 4 resulted in a 32.4% recovery yield based on the extraction value and degree of browning. To determine whether the protein ameliorated inflammation by inhibition of macrophage activation by lipopolysaccharides (LPS), we measured nitric oxide (NO), cyclooxygenase-2 (COX-2), and inducible nitric oxide synthase (iNOS) expression in LPS-stimulated raw 264.7 macrophage cells. The protein markedly inhibited the production of NO without cytotoxicity and reduced the expression level of COX-2 and iNOS protein through the regulation of mitogen-activated protein kinases (MAPKs) and nuclear factor kappa B ($NF-{\kappa}B$) signaling. These results suggested that protein derived from TM larvae could have potential applications in anti-inflammatory therapeutic agents and protein supplements.

The roles of Subcontractors' Entrepreneurship on the Relationship Commitment towards the Parent Companies (수급사업자의 기업가정신이 관계몰입을 유도하는 경로)

  • Nak Hwan Choi;Cheol Seob Byeon;Yong Gyun Lee
    • Asia Marketing Journal
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    • v.13 no.1
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    • pp.51-84
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    • 2011
  • It seems essential to examine the factors that may affect relationship commitment of subcontractors to parent companies in the industrial market in Korea in an effort to construct a win-win-type cooperative network among them. Lots of studies have been focusing on the consumer goods market. Relatively few studies have been focused on industrial market. In the industrial goods market subcontractors used to sell their parts or services only to a small number of parent companies in a large quantity, resulting in decisive control of subcontractors over the quality of parent companies' finished goods. This is why relationship between subcontractors and parent companies is extremely important. From this viewpoint, this study aims to survey and analyze empirically the paths leading to relationship commitment of subcontractors toward the parent companies which are required to incite them to build up a collaborative network by means of subcontractors' entrepreneurship. For this aim, market orientation effects of entrepreneurship as well as factors of performance and trust are particularly set forth as the bases of developing hypotheses in this study in order to explore the paths from entrepreneurship to relationship commitment as follows. First, the path of entrepreneurship-market orientation-communication-trust- relationship commitment; second, the path of entrepreneurship-market orientation-performance-relationship commitment; third, the path of entrepreneurship-market orientation-transaction specific asset investment -trust-relationship commitment; and fourth, the path in which the entrepreneurship is expected to promote direct transaction specific asset investment by parent companies to induce their trust and, eventually, relationship commitment of subcontractors. The outcomes of the empirical analysis in this study may be summed up as follows: First, the conclusions of preceding studies are also supported here by the fact that the entrepreneurship of subcontractors promotes their market orientation (hypothesis 9), indicating that the entrepreneurship can facilitate collection, proliferation of and response to market informations. On the contrary, however, the assumption that the entrepreneurship of subcontractors might directly accelerate transaction specific asset investment by parent companies (hypothesis 8) is rejected. Second, although the influence of subcontractors' entrepreneurship on parent companies' investment of assets peculiar to their transactions is not affirmed, the assumption is found to be supported that subcontractors' market orientation would expedite the parent companies' investment of assets peculiar to their transactions. Moreover, it is also confirmed that parent companies' investment of assets peculiar to transactions would promote subcontractors' trust toward the parent companies (hypothesis 6), signifying that parent companies may level up their trust in subcontractors when they make great amount of efforts to invest in the assets peculiar to transactions, not behaving opportunistically, Third, the hypotheses 4 and 5 also turn out to be supported by the analysis as the former assumes that market orientation could promote communication and the latter relates that the communication between subcontractors and parent companies would prompt trust, both results in affirming that market orientation could introduce open communication to speed up sharing of information and that sharing of information by way of communication might give an impetus to trust. Fourth, the assumption that subcontractors' market orientation would expedite performance (hypothesis 3) is also proved favorably to the significant level equivalent to that of preceding studies. Fifth, same as preceding studies, it is also verified in this study that the benefit (outcomes) awarded by parent companies to subcontractors will be a direct cause exercising a positive impact upon relationship commitment(hypothesis 2) and that the trust of subcontractors toward parent companies may have affirmative influence on the relationship commitment(hypothesis 1). Overall, the first, second and third paths are identified as being supported by the hypotheses among constituent factors, while the fourth path is deemed meaningless since it is shown that the entrepreneurship exercises no effects on parent companies' investment in the assets peculiar to transactions.

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Efficacy and Safety Evaluation of an Air Sterilizer Equipped With an Electrolytic Salt Catalyst for the Removal of Indoor Microbial Pollutants (염촉매 전기분해 공기살균기의 효능 평가)

  • Sun Nyoung Yu;Ho-Yeon Jeon;Bu Kyung Kim;Ae-Li Kim;Kyung Il Jung;Gye Rok Jeon;Soon Cheol Ahn
    • Journal of Life Science
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    • v.34 no.7
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    • pp.500-508
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    • 2024
  • Recently, there has been increasing interest in enhancing the indoor air quality, particularly in response to the growing utilization of public facilities. The focus of this study was on assessing the efficacy and safety of an air sterilizer equipped with electrolytic salt catalysts. To that end, we evaluated the antimicrobial activity of the vapor spraying from the air sterilizer and its cytotoxicity in condensed form on human cell lines (HaCaT, BEAS-2B, and THP-1). Against the test organisms, which comprised five bacterial strains (Staphylococcus aureus, Bacillus subtilis, Escherichia coli, Pseudomonas aeruginosa, Salmonella typhimurium) and one fungal strain (Candida albicans), the air sterilizer exhibited relatively high antimicrobial activities ranging from 10.89 to 73.98% following 1 and 3 hr of vapor spraying, which were notably time-dependent. Importantly, cytotoxicity assessments on human cells indicated no significant harmful effect even at a 1.0% concentration. Comprehensive safety evaluations included morphological observations, gene expression (Bcl-2, Bax) tests, and FACS analysis of intracellular ROS levels. Consistent with previous cytotoxicity findings, these estimates demonstrated no significant changes, highlighting the air sterilizer's safety and antimicrobial activities. In a simulated 20-hr operation within an indoor environment, the air sterilizer not only showed an 89.4% removal of total bacteria but also a 100.0% removal of Escherichia sp. and fungi. This research outlines the potential of the developed electrolytic salt catalyst air sterilizer to effectively remove indoor microbial pollutants without compromising human safety, underscoring the solution that it offers for improving indoor air quality.

Emoticon by Emotions: The Development of an Emoticon Recommendation System Based on Consumer Emotions (Emoticon by Emotions: 소비자 감성 기반 이모티콘 추천 시스템 개발)

  • Kim, Keon-Woo;Park, Do-Hyung
    • Journal of Intelligence and Information Systems
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    • v.24 no.1
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    • pp.227-252
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    • 2018
  • The evolution of instant communication has mirrored the development of the Internet and messenger applications are among the most representative manifestations of instant communication technologies. In messenger applications, senders use emoticons to supplement the emotions conveyed in the text of their messages. The fact that communication via messenger applications is not face-to-face makes it difficult for senders to communicate their emotions to message recipients. Emoticons have long been used as symbols that indicate the moods of speakers. However, at present, emoticon-use is evolving into a means of conveying the psychological states of consumers who want to express individual characteristics and personality quirks while communicating their emotions to others. The fact that companies like KakaoTalk, Line, Apple, etc. have begun conducting emoticon business and sales of related content are expected to gradually increase testifies to the significance of this phenomenon. Nevertheless, despite the development of emoticons themselves and the growth of the emoticon market, no suitable emoticon recommendation system has yet been developed. Even KakaoTalk, a messenger application that commands more than 90% of domestic market share in South Korea, just grouped in to popularity, most recent, or brief category. This means consumers face the inconvenience of constantly scrolling around to locate the emoticons they want. The creation of an emoticon recommendation system would improve consumer convenience and satisfaction and increase the sales revenue of companies the sell emoticons. To recommend appropriate emoticons, it is necessary to quantify the emotions that the consumer sees and emotions. Such quantification will enable us to analyze the characteristics and emotions felt by consumers who used similar emoticons, which, in turn, will facilitate our emoticon recommendations for consumers. One way to quantify emoticons use is metadata-ization. Metadata-ization is a means of structuring or organizing unstructured and semi-structured data to extract meaning. By structuring unstructured emoticon data through metadata-ization, we can easily classify emoticons based on the emotions consumers want to express. To determine emoticons' precise emotions, we had to consider sub-detail expressions-not only the seven common emotional adjectives but also the metaphorical expressions that appear only in South Korean proved by previous studies related to emotion focusing on the emoticon's characteristics. We therefore collected the sub-detail expressions of emotion based on the "Shape", "Color" and "Adumbration". Moreover, to design a highly accurate recommendation system, we considered both emotion-technical indexes and emoticon-emotional indexes. We then identified 14 features of emoticon-technical indexes and selected 36 emotional adjectives. The 36 emotional adjectives consisted of contrasting adjectives, which we reduced to 18, and we measured the 18 emotional adjectives using 40 emoticon sets randomly selected from the top-ranked emoticons in the KakaoTalk shop. We surveyed 277 consumers in their mid-twenties who had experience purchasing emoticons; we recruited them online and asked them to evaluate five different emoticon sets. After data acquisition, we conducted a factor analysis of emoticon-emotional factors. We extracted four factors that we named "Comic", Softness", "Modernity" and "Transparency". We analyzed both the relationship between indexes and consumer attitude and the relationship between emoticon-technical indexes and emoticon-emotional factors. Through this process, we confirmed that the emoticon-technical indexes did not directly affect consumer attitudes but had a mediating effect on consumer attitudes through emoticon-emotional factors. The results of the analysis revealed the mechanism consumers use to evaluate emoticons; the results also showed that consumers' emoticon-technical indexes affected emoticon-emotional factors and that the emoticon-emotional factors affected consumer satisfaction. We therefore designed the emoticon recommendation system using only four emoticon-emotional factors; we created a recommendation method to calculate the Euclidean distance from each factors' emotion. In an attempt to increase the accuracy of the emoticon recommendation system, we compared the emotional patterns of selected emoticons with the recommended emoticons. The emotional patterns corresponded in principle. We verified the emoticon recommendation system by testing prediction accuracy; the predictions were 81.02% accurate in the first result, 76.64% accurate in the second, and 81.63% accurate in the third. This study developed a methodology that can be used in various fields academically and practically. We expect that the novel emoticon recommendation system we designed will increase emoticon sales for companies who conduct business in this domain and make consumer experiences more convenient. In addition, this study served as an important first step in the development of an intelligent emoticon recommendation system. The emotional factors proposed in this study could be collected in an emotional library that could serve as an emotion index for evaluation when new emoticons are released. Moreover, by combining the accumulated emotional library with company sales data, sales information, and consumer data, companies could develop hybrid recommendation systems that would bolster convenience for consumers and serve as intellectual assets that companies could strategically deploy.