• Title/Summary/Keyword: 선호도 평가

Search Result 2,127, Processing Time 0.033 seconds

Individual Thinking Style leads its Emotional Perception: Development of Web-style Design Evaluation Model and Recommendation Algorithm Depending on Consumer Regulatory Focus (사고가 시각을 바꾼다: 조절 초점에 따른 소비자 감성 기반 웹 스타일 평가 모형 및 추천 알고리즘 개발)

  • Kim, Keon-Woo;Park, Do-Hyung
    • Journal of Intelligence and Information Systems
    • /
    • v.24 no.4
    • /
    • pp.171-196
    • /
    • 2018
  • With the development of the web, two-way communication and evaluation became possible and marketing paradigms shifted. In order to meet the needs of consumers, web design trends are continuously responding to consumer feedback. As the web becomes more and more important, both academics and businesses are studying consumer emotions and satisfaction on the web. However, some consumer characteristics are not well considered. Demographic characteristics such as age and sex have been studied extensively, but few studies consider psychological characteristics such as regulatory focus (i.e., emotional regulation). In this study, we analyze the effect of web style on consumer emotion. Many studies analyze the relationship between the web and regulatory focus, but most concentrate on the purpose of web use, particularly motivation and information search, rather than on web style and design. The web communicates with users through visual elements. Because the human brain is influenced by all five senses, both design factors and emotional responses are important in the web environment. Therefore, in this study, we examine the relationship between consumer emotion and satisfaction and web style and design. Previous studies have considered the effects of web layout, structure, and color on emotions. In this study, however, we excluded these web components, in contrast to earlier studies, and analyzed the relationship between consumer satisfaction and emotional indexes of web-style only. To perform this analysis, we collected consumer surveys presenting 40 web style themes to 204 consumers. Each consumer evaluated four themes. The emotional adjectives evaluated by consumers were composed of 18 contrast pairs, and the upper emotional indexes were extracted through factor analysis. The emotional indexes were 'softness,' 'modernity,' 'clearness,' and 'jam.' Hypotheses were established based on the assumption that emotional indexes have different effects on consumer satisfaction. After the analysis, hypotheses 1, 2, and 3 were accepted and hypothesis 4 was rejected. While hypothesis 4 was rejected, its effect on consumer satisfaction was negative, not positive. This means that emotional indexes such as 'softness,' 'modernity,' and 'clearness' have a positive effect on consumer satisfaction. In other words, consumers prefer emotions that are soft, emotional, natural, rounded, dynamic, modern, elaborate, unique, bright, pure, and clear. 'Jam' has a negative effect on consumer satisfaction. It means, consumer prefer the emotion which is empty, plain, and simple. Regulatory focus shows differences in motivation and propensity in various domains. It is important to consider organizational behavior and decision making according to the regulatory focus tendency, and it affects not only political, cultural, ethical judgments and behavior but also broad psychological problems. Regulatory focus also differs from emotional response. Promotion focus responds more strongly to positive emotional responses. On the other hand, prevention focus has a strong response to negative emotions. Web style is a type of service, and consumer satisfaction is affected not only by cognitive evaluation but also by emotion. This emotional response depends on whether the consumer will benefit or harm himself. Therefore, it is necessary to confirm the difference of the consumer's emotional response according to the regulatory focus which is one of the characteristics and viewpoint of the consumers about the web style. After MMR analysis result, hypothesis 5.3 was accepted, and hypothesis 5.4 was rejected. But hypothesis 5.4 supported in the opposite direction to the hypothesis. After validation, we confirmed the mechanism of emotional response according to the tendency of regulatory focus. Using the results, we developed the structure of web-style recommendation system and recommend methods through regulatory focus. We classified the regulatory focus group in to three categories that promotion, grey, prevention. Then, we suggest web-style recommend method along the group. If we further develop this study, we expect that the existing regulatory focus theory can be extended not only to the motivational part but also to the emotional behavioral response according to the regulatory focus tendency. Moreover, we believe that it is possible to recommend web-style according to regulatory focus and emotional desire which consumers most prefer.

Major Class Recommendation System based on Deep learning using Network Analysis (네트워크 분석을 활용한 딥러닝 기반 전공과목 추천 시스템)

  • Lee, Jae Kyu;Park, Heesung;Kim, Wooju
    • Journal of Intelligence and Information Systems
    • /
    • v.27 no.3
    • /
    • pp.95-112
    • /
    • 2021
  • In university education, the choice of major class plays an important role in students' careers. However, in line with the changes in the industry, the fields of major subjects by department are diversifying and increasing in number in university education. As a result, students have difficulty to choose and take classes according to their career paths. In general, students choose classes based on experiences such as choices of peers or advice from seniors. This has the advantage of being able to take into account the general situation, but it does not reflect individual tendencies and considerations of existing courses, and has a problem that leads to information inequality that is shared only among specific students. In addition, as non-face-to-face classes have recently been conducted and exchanges between students have decreased, even experience-based decisions have not been made as well. Therefore, this study proposes a recommendation system model that can recommend college major classes suitable for individual characteristics based on data rather than experience. The recommendation system recommends information and content (music, movies, books, images, etc.) that a specific user may be interested in. It is already widely used in services where it is important to consider individual tendencies such as YouTube and Facebook, and you can experience it familiarly in providing personalized services in content services such as over-the-top media services (OTT). Classes are also a kind of content consumption in terms of selecting classes suitable for individuals from a set content list. However, unlike other content consumption, it is characterized by a large influence of selection results. For example, in the case of music and movies, it is usually consumed once and the time required to consume content is short. Therefore, the importance of each item is relatively low, and there is no deep concern in selecting. Major classes usually have a long consumption time because they have to be taken for one semester, and each item has a high importance and requires greater caution in choice because it affects many things such as career and graduation requirements depending on the composition of the selected classes. Depending on the unique characteristics of these major classes, the recommendation system in the education field supports decision-making that reflects individual characteristics that are meaningful and cannot be reflected in experience-based decision-making, even though it has a relatively small number of item ranges. This study aims to realize personalized education and enhance students' educational satisfaction by presenting a recommendation model for university major class. In the model study, class history data of undergraduate students at University from 2015 to 2017 were used, and students and their major names were used as metadata. The class history data is implicit feedback data that only indicates whether content is consumed, not reflecting preferences for classes. Therefore, when we derive embedding vectors that characterize students and classes, their expressive power is low. With these issues in mind, this study proposes a Net-NeuMF model that generates vectors of students, classes through network analysis and utilizes them as input values of the model. The model was based on the structure of NeuMF using one-hot vectors, a representative model using data with implicit feedback. The input vectors of the model are generated to represent the characteristic of students and classes through network analysis. To generate a vector representing a student, each student is set to a node and the edge is designed to connect with a weight if the two students take the same class. Similarly, to generate a vector representing the class, each class was set as a node, and the edge connected if any students had taken the classes in common. Thus, we utilize Node2Vec, a representation learning methodology that quantifies the characteristics of each node. For the evaluation of the model, we used four indicators that are mainly utilized by recommendation systems, and experiments were conducted on three different dimensions to analyze the impact of embedding dimensions on the model. The results show better performance on evaluation metrics regardless of dimension than when using one-hot vectors in existing NeuMF structures. Thus, this work contributes to a network of students (users) and classes (items) to increase expressiveness over existing one-hot embeddings, to match the characteristics of each structure that constitutes the model, and to show better performance on various kinds of evaluation metrics compared to existing methodologies.

An Exploratory Study on Channel Equity of Electronic Goods (가전제품 소비자의 Channel Equity에 관한 탐색적 연구)

  • Suh, Yong-Gu;Lee, Eun-Kyung
    • Journal of Global Scholars of Marketing Science
    • /
    • v.18 no.3
    • /
    • pp.1-25
    • /
    • 2008
  • Ⅰ. Introduction Retailers in the 21st century are being told that future retailers are those who can execute seamless multi-channel access. The reason is that retailers should be where shoppers want them, when they want them anytime, anywhere and in multiple formats. Multi-channel access is considered one of the top 10 trends of all business in the next decade (Patricia T. Warrington, et al., 2007) And most firms use both direct and indirect channels in their markets. Given this trend, we need to evaluate a channel equity more systematically than before as this issue is expected to get more attention to consumers as well as to brand managers. Consumers are becoming very much confused concerning the choice of place where they shop for durable goods as there are at least 6-7 retail options. On the other hand, manufacturers have to deal with category killers, their dealers network, Internet shopping malls, and other avenue of distribution channels and they hope their retail channel behave like extensions of their own companies. They would like their products to be foremost in the retailer's mind-the first to be proposed and effectively communicated to potential customers. To enable this hope to come reality, they should know each channel's advantages and disadvantages from consumer perspectives. In addition, customer satisfaction is the key determinant of retail customer loyalty. However, there are only a few researches regarding the effects of shopping satisfaction and perceptions on consumers' channel choices and channels. The purpose of this study was to assess Korean consumers' channel choice and satisfaction towards channels they prefer to use in the case of electronic goods shopping. Korean electronic goods retail market is one of good example of multi-channel shopping environments. As the Korea retail market has been undergoing significant structural changes since it had opened to global retailers in 1996, new formats such as hypermarkets, Internet shopping malls and category killers have arrived for the last decade. Korean electronic goods shoppers have seven major channels : (1)category killers (2) hypermarket (3) manufacturer dealer shop (4) Internet shopping malls (5) department store (6) TV home-shopping (7) speciality shopping arcade. Korean retail sector has been modernized with amazing speed for the last decade. Overall summary of major retail channels is as follows: Hypermarket has been number 1 retailer type in sales volume from 2003 ; non-store retailing has been number 2 from 2007 ; department store is now number 3 ; small scale category killers are growing rapidly in the area of electronics and office products in particular. We try to evaluate each channel's equity using a consumer survey. The survey was done by telephone interview with 1000 housewife who lives nationwide. Sampling was done according to 2005 national census and average interview time was 10 to 15 minutes. Ⅱ. Research Summary We have found that seven major retail channels compete with each other within Korean consumers' minds in terms of price and service. Each channel seem to have its unique selling points. Department stores were perceived as the best electronic goods shopping destinations due to after service. Internet shopping malls were perceived as the convenient channel owing to price checking. Category killers and hypermarkets were more attractive in both price merits and location conveniences. On the other hand, manufacturers dealer networks were pulling customers mainly by location and after service. Category killers and hypermarkets were most beloved retail channel for Korean consumers. However category killers compete mainly with department stores and shopping arcades while hypermarkets tend to compete with Internet and TV home shopping channels. Regarding channel satisfaction, the top 3 channels were service-driven retailers: department stores (4.27); dealer shop (4.21); and Internet shopping malls (4.21). Speciality shopping arcade(3.98) were the least satisfied channels among Korean consumers. Ⅲ. Implications We try to identify the whole picture of multi-channel retail shopping environments and its implications in the context of Korean electronic goods. From manufacturers' perspectives, multi-channel may cause channel conflicts. Furthermore, inter-channel competition draws much more attention as hypermarkets and category killers have grown rapidly in recent years. At the same time, from consumers' perspectives, 'buy where' is becoming an important buying decision as it would decide the level of shopping satisfaction. We need to develop the concept of 'channel equity' to manage multi-channel distribution effectively. Firms should measure and monitor their prime channel equity in regular basis to maximize their channel potentials. Prototype channel equity positioning map has been developed as follows. We expect more studies to develop the concept of 'channel equity' in the future.

  • PDF

A Study of Nutritional Intake, Eating Habit, Iron Status of Urban and Rural Middle School Girls (도시와 농촌 여중생의 영양섭취상태, 식습관 및 철영양상태 연구)

  • Hong, Soon-Myung;Seo, Yeong-Eun;Hwang, Hye-Jin
    • Journal of the Korean Society of Food Science and Nutrition
    • /
    • v.33 no.10
    • /
    • pp.1634-1640
    • /
    • 2004
  • This study was designed to compare the nutritional intake and iron nutritional status between urban and rural middle school girls. Along with a questionnaire, blood samples were obtained from 311 middle school girls (urban 129 girls, rural 182 girls). Nutrient intakes were measured with a convenient method, and clinical symptoms relating anemia was investigated by 4-point Likert scale. For the nutrient intake, the total energy intake was 1722.2 kcal (82.0% of RDA) for the urban group and 1649.5 kcal (78.6% of RDA) for rural group. The rural group showed significantly lower level than the urban group in all nutrients except fat, carbohydrate and total energy intake. Regarding the food frequency, students from the rural group marked significantly lower intake of milk (p<0.00l), kimchi (p<0.05), fruit (p<0.05), tofu, bean (p<0.00l) than the urban group. For every clinical finding regarding anemia, the rural group marked higher value than the urban group but the difference was not significant. The hemoglobin concentration of urban group was 13.28 g/dL, and rural group showed 12.51 g/dL which was significantly lower than urban group (p<0.00l). The hematocrit rate was 37.82% for the urban group and 38.13% for the rural group and there was no significant difference between two groups. The red blood cell (RBC) count of the rural group was significantly lower than the urban group (p<0.00l). Evaluating with the iron deficiency standard which is less than 12 g/dL, the urban group was 6.2% and the rural group was 34.6% thus the deficiency rate was significantly higher in the rural group. This study showed that nutrient and iron status of the girls of rural group is not as good as the urban group. As middle school girls require high level of iron absorption due to blood loss which occurs during abrupt physical growth and menstruation, dietary counselling is required to enhance the iron status. When iron deficiency is serious, they need to take more positive action such as iron supplement in addition to food-iron fortification.

A Study on Food Habits and Nutrient Intakes according to BMI in Food and Nutrition Major and Non-major Female Students in Kyungnam University (식품영양전공과 비전공 여대생의 BMI에 따른 식습관 및 영양소 섭취 상태에 관한 연구 -경남대학교를 중심으로-)

  • Seo, Eun-Hee
    • Korean Journal of Community Nutrition
    • /
    • v.19 no.4
    • /
    • pp.297-316
    • /
    • 2014
  • Objectives: This study was performed to investigate the body image, food habits, nutrition knowledge, food intake frequency, nutrient intakes of female university students in Masan. Methods: Two groups (n = 302, nutrition major: 147, non-major: 155) were classified into underweight, normal weight and overweight/obesity groups according to BMI respectively. Results: Height and weight of all subjects were 161.5 cm, 53.2 kg and were 161.5 cm, 55.1 kg, 161.5 cm, 51.3 kg in major and non-major female students, respectively. The BMI and body weight were significantly different (p < 0.001). Significantly higher proportions of underweight students in both study groups had perceived as 'normal' or 'fat' (p < 0.001). Higher proportion of the subjects skipped breakfast and main reason was no time to eat. Nutrition knowledge score was significantly higher in major than in non-major subjects (p < 0.001). Fish intake frequency score was significantly higher in non-majors, while the vegetable intake frequency score was significantly higher in majors. Nutrient intakes were significantly higher the majors compared to non-majors, particularly the intake of calcium (p < 0.05), zinc (p < 0.001), vitamin C (p < 0.001) and vitamin E (p < 0.01). Subjects in both groups did not have adequate nutrient intakes compared to KDRIs. BMI showed a positive correlation with body image, body weight and nutrition knowledge score (p < 0.01). Conclusions: These results suggest that systematic nutrition education program which can be applied in real life is important for the formation of correct choices of food and good eating habits.

Clinical and radiographic evaluation of $Neoplan^{(R)}$ implant with a sandblasted and acid-etched surface and external connection (SLA 표면 처리 및 외측 연결형의 국산 임플랜트에 대한 임상적, 방사선학적 평가)

  • An, Hee-Suk;Moon, Hong-Suk;Shim, Jun-Sung;Cho, Kyu-Sung;Lee, Keun-Woo
    • The Journal of Korean Academy of Prosthodontics
    • /
    • v.46 no.2
    • /
    • pp.125-136
    • /
    • 2008
  • Statement of problem: Since the concept of osseointegration in dental implants was introduced by $Br{{\aa}}nemark$ et al, high long-term success rates have been achieved. Though the use of dental implants have increased dramatically, there are few studies on domestic implants with clinical and objective long-term data. Purpose: The aim of this retrospective study was to provide long-term data on the $Neoplan^{(R)}$ implant, which features a sandblasted and acid-etched surface and external connection. Material and methods: 96 $Neoplan^{(R)}$ implants placed in 25 patients in Yonsei University Hospital were examined to determine the effect of the factors on marginal bone loss, through clinical and radiographic results during 18 to 57 month period. Results: 1. Out of a total of 96 implants placed in 25 patients, two fixtures were lost, resulting in 97.9% of cumulative survival rate. 2. Throughout the study period, the survival rates were 96.8% in the maxilla and 98.5% in the mandible. The survival rates were 97.6% in the posterior regions and 100% in the anterior regions. 3. The mean bone loss for the first year after prosthesis placement and the mean annual bone loss after the first year for men were significantly higher than that of women (P<0.05). 4. The group of partial edentulism with no posterior teeth distal to the implant prosthesis showed significantly more bone loss compared to the group of partial edentulism with presence of posterior teeth distal to the implant prosthesis in terms of mean bone loss for the first year and after the first year (P<0.05). 5. The mean annual bone loss after the first year was more pronounced in posterior regions compared to anterior regions (P<0.05). 6. No significant difference in marginal bone loss was found in the following factors: jaws, type of prostheses, type of opposing dentition, and submerged /non-submerged implants (P<0.05). Conclusion: On the basis of these results, the factors influencing marginal bone loss were gender, type of edentulism, and location in the arch, while the factors such as arch, type of prostheses, type of opposing dentition, submerged / non- submerged implants had no significant effect on bone loss. In the present study, the cumulative survival rate of the $Neoplan^{(R)}$ implant with a sandblasted and acid-etched surface was 97.9% up to a maximum 57-month period. Further long-term investigations for this type of implant system and evaluation of other various domestic implant systems are needed in future studies.

Comparative analysis of Glomerular Filtration Rate measurement and estimated glomerular filtration rate using 99mTc-DTPA in kidney transplant donors. (신장이식 공여자에서 99mTc-DTPA를 이용한 Glomerular Filtration Rate 측정과 추정사구체여과율의 비교분석)

  • Cheon, Jun Hong;Yoo, Nam Ho;Lee, Sun Ho
    • The Korean Journal of Nuclear Medicine Technology
    • /
    • v.25 no.2
    • /
    • pp.35-40
    • /
    • 2021
  • Purpose Glomerular filtration rate(GFR) is an important indicator for the diagnosis, treatment, and follow-up of kidney disease and is also used by healthy individuals for drug use and evaluating kidney function in donors. The gold standard method of the GFR test is to measure by continuously injecting the inulin which is extrinsic marker, but it takes a long time and the test method is complicated. so, the method of measuring the serum concentration of creatinine is used. Estimated glomerular filtration rate (eGFR) is used instead. However, creatinine is known to be affected by age, gender, muscle mass, etc. eGFR formulas that are currently used include the Cockroft-Gault formula, the modification of diet in renal disease (MDRD) formula, and the chronic kidney disease epidemilogy collaboration (CKD-EPI) formula for adults. For children, the Schwartz formula is used. Measurement of GFR using 51Cr-EDTA (diethylenetriamine tetraacetic acid), 99mTc-DTPA (diethylenetriamine pentaacetic acid) can replace inulin and is currently in use. Therefore, We compared the GFR measured using 99mTc-DTPA with the eGFR using CKD-EPI formula. Materials and Methods For 200 kidney transplant donors who visited Asan medical center.(96 males, 104 females, 47.3 years ± 12.7 years old) GFR was measured using plasma(Two-plasma-sample-method, TPSM) obtained by intravenous administration of 99mTc-DTPA(0.5mCi, 18.5 MBq). eGFR was derived using CKD-EPI formula based on serum creatinine concentration. Results GFR average measured using 99mTc-DTPA for 200 kidney transplant donors is 97.27±19.46(ml/min/1.73m2), and the eGFR average value using the CKD-EPI formula is 96.84±17.74(ml/min/1.73m2), The concentration of serum creatinine is 0.84±0.39(mg/dL). Regression formula of 99mTc-DTPA GFR for serum creatinine-based eGFR was Y = 0.5073X + 48.186, and the correlation coefficient was 0.698 (P<0.01). Difference (%) was 1.52±18.28. Conclusion The correlation coefficient between the 99mTc-DTPA and the eGFR derived on serum creatinine concentration was confirmed to be moderate. This is estimated that eGFR is affected by external factors such as age, gender, and muscle mass and use of formulas made for kidney disease patients. By using 99mTc-DTPA, we can provide reliable GFR results, which is used for diagnosis, treatment and observation of kidney disease, and kidney evaluation of kidney transplant patients.

Shelf-Life Extension of Sing Sing Hoe (Fresh Sliced Raw Fish) by Frozen Storage (냉동저장을 통한 싱싱회 저장기간 연장에 관한 연구)

  • Park, Jin-Il;Yoon, So-Mi;Yoon, Ho-Dong;Park, Hee-Yeon;Byun, Han-Seok;Jang, Mi-Soon
    • Food Science and Preservation
    • /
    • v.16 no.6
    • /
    • pp.824-829
    • /
    • 2009
  • Changes in pH, viable microbial count, chemical freshness, texture, and sensory qualities of Sing Sing Hoe (SSH, fresh-sliced raw fish) were measured over 15 days at $4^{\circ}C$, $-20^{\circ}C$, and $-80^{\circ}C$. The initial pH of SSH was 6.25 at all three storage temperatures, and pH increased slightly after 12 days to pH 6.48 and pH 6.55 at $-20^{\circ}C$ and $-80^{\circ}C$, respectively. The range in viable cell count was 104-106 CFU/g, regardless of storage temperature. The initial content of volatile basic nitrogen (VBN) was 5.8 mg/100 g and became 8.2 mg/100 g or less, and 7.9 mg/100 g or less after 15 days at $-20^{\circ}C$ and $-80^{\circ}C$, respectively. However, pH and VBN values increased significantly after 3 days of storage at $4^{\circ}C$. At this temperature, the K-value was 22.3% after 6 days and 40% or more after 15 days. At $-20^{\circ}C$, the K-value was 9.6% or less after 6 days and 21% or less after 15 days of storage. At $-80^{\circ}C$, the K-value was 8.5% or less after 9 days and 20% or less after 15 days of storage. Compared with the K-value of live fish muscle (10%), freshness similar to that of live fish was maintained for 6 days under both $-20^{\circ}C$ and $-80^{\circ}C$ storage conditions. There was no significant change in texture during storage of SSH at $-20^{\circ}C$ or $-80^{\circ}C$, but SSH stored at $4^{\circ}C$ showed a decrease in texture quality during storage. Sensory scores were high for material stored for up to 3 days at $4^{\circ}C$ and 6 days at $-20^{\circ}C$ or $-80^{\circ}C$. The overall freshness of SSH was maintained for up to 6 days, in comparison with fresh-sliced raw fish, under both frozen storage conditions.

Effects of Detoxified Sulfur as a Feed Supplement on in Vitro Rumen Fermentation and Methane Mitigation (제독 유황의 반추위 발효성상 및 메탄 저감 효과 연구)

  • Kim, Seon-Ho;Islam, Mahfuzul;Biswas, Ashraf Ali;Cho, Kwang-Keun;Lee, Sang-Suk
    • Journal of Life Science
    • /
    • v.30 no.9
    • /
    • pp.743-748
    • /
    • 2020
  • Sulfate is a reductant that competes for electrons and may lower CH4 production in the rumen. This study was designed to evaluate the beneficial effect of detoxified sulfur powder supplementation on in vitro rumen fermentation and methane mitigation. A ruminally cannulated Holstein Friesian cow was used as a rumen fluid source, and commercial pelleted concentrate was used as a substrate at 1 g dry matter. Treatments included the addition of detoxified sulfur powder at the rate of 0% (Control), 0.2% (T1), 0.4% (T2), 0.6% (T3), 0.8% (T4), and 1.0% (T5) as dry matter (DM) basis. The pH, total gas (TG), methane (CH4) production, DM digestibility, organic matter (OM) digestibility, and volatile fatty acids (VFA) production were analyzed after 12 hr of incubation. The results showed that CH4 production was significantly lowest in T1 (13.78 ml) but highest in the control (20.16 ml). Insignificantly higher total VFA was observed in control and T1 (64.99 and 64.28 mM, respectively) compared to other treatments after 12 hr of incubation. After 12 hr of incubation, the significantly lowest acetate:propionate was observed in T1 (1.90) while the highest was observed in T4 (2.44). However, no significant differences were recorded for pH, TG, DM digestibility, OM digestibility, acetate, propionate, and butyrate between the control and T1. Total number of bacterial DNA copies was significantly lower in the treatment group than the control. Therefore, it can be concluded from this study that detoxified sulfur at 0.2% inclusion level is optimal for production performance and ruminal CH4 mitigation.

Ecological Characteristics of Periphyton Community in a Small Mountain Stream (Buso) Inflowing Thermal Wastewater Effluent, Korea (온배수가 유입되는 계류 (부소천)에서 부착조류의 생태학적 특성)

  • Jeon, Gyeonghye;Kim, Nan-Young;Hwang, Soon-Jin;Shin, Jae-Ki
    • Korean Journal of Ecology and Environment
    • /
    • v.50 no.2
    • /
    • pp.216-237
    • /
    • 2017
  • Thermal effluent of the hot spring has long been a field of interest in the relationship between temperature gradient and freshwater algae in geology, limnology and aquatic ecology throughout the world. On the other hand, many artificial hot springs have been developed in Korea, but the research on them has not been still active. This study was performed every month from December 2015 to September 2016, to elucidate the spatiotemporal effects of thermal wastewater effluent (TWE) on the ecosystem of benthic algal assemblage in four stations(BSU (upstream), HSW (hot spring wastewater outlet), BSD1~2 (downstream)) of the upstream reach of the Buso Stream, a tributary located in the Hantan River basin. During the survey, the influencing distance of temperature on TWE was <1.0 km, and it was the main source of N P nutrients at the same time. The effects of TWE were dominant at low temperature and dry season (December~March), but it was weak at high temperature and wet season (July~September), reflecting some seasonal characteristics. Under these circumstances, the attached algal communities were identified to 59 genera and 143 species. Of these, the major phylum included 21 genera 83 species of diatoms(58.0%), 9 genera 21 species of blue-green algae (14.7%) and 25 genera 32 species of green algae (22.4%), respectively. The spatiotemporal distribution of them was closely related to water temperature ($5^{\circ}C$ and $15^{\circ}C$) and current ($0.2m\;s^{-1}$ and $0.8m\;s^{-1}$). In the basic environment maintaining a high water temperature throughout the year round, the flora favoring high affinity to $PO_4$ in the water body or preferring stream habitat of abundant $NO_3-PO_4$ was dominant. As a result, when compared with the outcomes of previous algal ecology studies conducted in Korea, the Buso Stream was evaluated as a serious polluted state due to persistent excess nutrient supply and high thermal pollution throughout the year round by TWE. It can be regarded as a dynamic ecosystem in which homogeneity (Summer~Autumn) and heterogeneity (Winter~Spring) are repeated between upstream and downstream.