• 제목/요약/키워드: Trends in research

Search Result 7,791, Processing Time 0.054 seconds

A Study of Rent Determinants of Small and Medium-Sized Office Buildings in Seoul Using a Dynamic Panel Model: Focusing on CBD and GBD Comparison (동적패널모형을 활용한 서울시 중소형 오피스 빌딩 임대료 결정 요인 연구: CBD(도심권)와 GBD(강남권) 비교를 중심으로)

  • NaRa Kim;JinSeok Yu;Jongjin Kim
    • Land and Housing Review
    • /
    • v.14 no.4
    • /
    • pp.47-62
    • /
    • 2023
  • Using the dynamic panel model, this study investigates rent determinants for small and medium-sized office buildings in Korea's CBD and Gangnam areas, key business districts. The results reveal that rents for small and medium-sized office buildings in CBD and Gangnam areas are influenced by macroeconomic fluctuations and characteristics of buildings and locations, suggesting a market with both spatial consumer and investment goods attributes. There are several investment implications as follows. First, even if the location in the CBD area is advantageous, the practical limitations in renovating aging small and medium-sized office buildings must be taken into account when investing. Second, parking conditions are a key factor influencing rent prices in CBD areas, so evaluating the parking facilities and improvement potential of small and medium-sized office buildings is essential for investors. Finally, due to the high sensitivity of Gangnam's small and medium-sized office market to macroeconomic trends, it's vital to prioritize monetary policy shifts as a key factor in investment decisions.

Machine- and Deep Learning Modelling Trends for Predicting Harmful Cyanobacterial Cells and Associated Metabolites Concentration in Inland Freshwaters: Comparison of Algorithms, Input Variables, and Learning Data Number (담수 유해남조 세포수·대사물질 농도 예측을 위한 머신러닝과 딥러닝 모델링 연구동향: 알고리즘, 입력변수 및 학습 데이터 수 비교)

  • Yongeun Park;Jin Hwi Kim;Hankyu Lee;Seohyun Byeon;Soon-Jin Hwang;Jae-Ki Shin
    • Korean Journal of Ecology and Environment
    • /
    • v.56 no.3
    • /
    • pp.268-279
    • /
    • 2023
  • Nowadays, artificial intelligence model approaches such as machine and deep learning have been widely used to predict variations of water quality in various freshwater bodies. In particular, many researchers have tried to predict the occurrence of cyanobacterial blooms in inland water, which pose a threat to human health and aquatic ecosystems. Therefore, the objective of this study were to: 1) review studies on the application of machine learning models for predicting the occurrence of cyanobacterial blooms and its metabolites and 2) prospect for future study on the prediction of cyanobacteria by machine learning models including deep learning. In this study, a systematic literature search and review were conducted using SCOPUS, which is Elsevier's abstract and citation database. The key results showed that deep learning models were usually used to predict cyanobacterial cells, while machine learning models focused on predicting cyanobacterial metabolites such as concentrations of microcystin, geosmin, and 2-methylisoborneol (2-MIB) in reservoirs. There was a distinct difference in the use of input variables to predict cyanobacterial cells and metabolites. The application of deep learning models through the construction of big data may be encouraged to build accurate models to predict cyanobacterial metabolites.

Application and Development Strategies of a Secure Real-Time Operating System in Weapon Systems within the Defense Sector (국방분야 보안 RTOS의 무기체계 적용 및 발전 방안)

  • Sang-Seung Lee;Keun-Ha Choi;Seung-Hyeon Hwang;Hyun-Ji Kim;Kyung-Deok Seo;Hwa-Eun Seong
    • The Journal of the Convergence on Culture Technology
    • /
    • v.10 no.5
    • /
    • pp.189-193
    • /
    • 2024
  • As cyber threats increase in the defense sector, the security of weapon system software is becoming increasingly important. Currently, most of the embedded software installed in domestic weapon systems operates based on foreign real-time operating systems(RTOS) that have no security. As a result, the localization and security enhancement of embedded software for weapon systems have emerged as urgent tasks. This study aims to propose the application and development strategies of secure RTOS for weapon systems. To this end, we examined the technological trends of domestic and foreign RTOS and secure RTOS, and analyzed the problems of current embedded software in weapon systems. The results revealed major issues such as low localization, vulnerability to cyber attacks, difficulty in maintenance, increased costs, and loss of opportunities for accumulating technological capabilities. An investigation of the current status of embedded software applied to existing weapon systems found that embedded SW are in operation across all fields, including maneuver, firepower, protection, command and control, communication, naval vessels, and aircraft. Among them, 99% rely on foreign RTOS such as VxWorks. A review of the core functions and applicability of secure RTOS to weapon systems suggests that it can be applied to key areas requiring real-time performance and security, such as fire control, navigation devices, and flight control in existing and future weapon systems. However, ensuring performance and reliability, securing verification and compatibility, and systematic government support were raised as prerequisites.

Effects of Total Mixed Rations on Ruminal Characteristics, Digestibility and Beef Production of Hanwoo Steers (섬유질배합사료 급여가 비육후기 거세한우의 반추위 발효성상, 소화율 및 산육성에 미치는 영향)

  • Kim, K.H.;Kim, K.S.;Lee, S.C.;Oh, Y.G.;Chung, C.S.;Kim, K.J.
    • Journal of Animal Science and Technology
    • /
    • v.45 no.3
    • /
    • pp.387-396
    • /
    • 2003
  • This experiment was carried out to compare the effects of feeding commercial formula feed and rice straw separately (control) versus a total mixed ration (TMR) on productivity of Hanwoo steers in late stage of fattening and on ruminal fermentation characteristics and digestibilities. Ruminal digesta from the cannulated cattle were sampled at 0, 1, 2, 3, 5, 8 hour after feeding. The steers fed TMR consumed 7.4kg per day and there was no difference between feeding systems. Daily weight gain was not significantly (P>0.05) between feeding systems, however, TMR group showed lower daily gain than control group. The amount of feed consumption per kg weight gain was higher in TMR group than control group (10.5kg and 9.7kg, respectively), resulting in a greater efficiency of feed utilization for gain. In the result of appearance rates of quality grade A were 33% higher for TMR group than those in control group. Appearance rates of grade 1 showed 56% and 75% when fed the control and TMR, respectively. Digestibilities of dry matter, crude protein, crude fiber and gross energy for TMR treatment were significantly higher (P<0.01) than those of control. Prior to feeding (0 h) and each subsequent hour, the TMR resulted in higher rumen pH (P<0.05) when compared with control ration. The concentration of NH3-N for TMR treatment maintained at higher level up to 8hr after feeding, especially increased up to 28.2mg/$d\ell$ during 1-2 hour which was two times (P<0.05) more than control. The amount of total VFA showed same trends between feeding systems. However, the ratios of branched chained fatty acid such as iso-butyric acid and iso-valeric acid for TMR treatment were significantly(P<0.01) higher than control for 3-5hr. Results showed that TMR in these trials is effective feeding system for fattening Hanwoo steers in the respect of ruminal characteristics, total tract digestibility and productivities.

Mycorrhizae, mushrooms, and research trends in Korea (균근과 버섯 그리고 국내 연구동향)

  • An, Gi-Hong;Cho, Jae-Han;Han, Jae-Gu
    • Journal of Mushroom
    • /
    • v.18 no.1
    • /
    • pp.1-9
    • /
    • 2020
  • Mycorrhiza refers to the association between a plant and a fungus colonizing the cortical tissue of the plant's roots during periods of active plant growth. The benefits afforded by plants from mycorrhizal symbioses can be characterized either agronomically, based on increased growth and yield, or ecologically, based on improved fitness (i.e., reproductive ability). In either case, the benefit accrues primarily because mycorrhizal fungi form a critical linkage between plant roots and the soil. The soilborne or extramatrical hyphae take up nutrients from the soil solution and transport them to the root. This mycorrhizae-mediated mechanism increases the effective absorptive surface area of the plant. There are seven major types of mycorrhizae along with mycoheterotrophy: endomycorrhizae (arbuscular mycorrhizae, AM), ectomycorrhizae (EM), ectendomycorrhizae, monotropoid, arbutoid, orchid, and ericoid. Endomycorrhizal fungi form arbuscules or highly branched structures within root cortical cells, giving rise to arbuscular mycorrhiza, which may produce extensive extramatrical hyphae and significantly increase phosphorus inflow rates in the plants they colonize. Ectomycorrhizal fungi may produce large quantities of hyphae on the root and in the soil; these hyphae play a role in absorption and translocation of inorganic nutrients and water, and also release nutrients from litter layers by producing enzymes involved in mineralization of organic matters. Over 4,000 fungal species, primarily belonging to Basidiomycotina and to a lesser extent Ascomycotina, are able to form ectomycorrhizae. Many of these fungi produce various mushrooms on the forest floor that are traded at a high price. In this paper, we discuss the benefits, nutrient cycles, and artificial cultivation of mycorrhizae in Korea.

The Influence of Art-provoked Affect on Product and Product Attributes Evaluation (명화(名畵)에서 유발된 감정이 차용된 제품과 제품속성 평가에 미치는 영향)

  • Kim, Hanku;Jung, Bohee;Chu, Wujin
    • Asia Marketing Journal
    • /
    • v.13 no.2
    • /
    • pp.99-130
    • /
    • 2011
  • In recent years, a new way of differentiating product design has emerged -better known as 'masterpiece marketing,' this is a strategy where famous art pieces are borrowed on to product designs. Because the recent trends of well-being and LOHAS have encouraged the consumers' desires to enjoy culture and live a more opulent lifestyle, famous and notable paintings have grown to be more of "approachable masterpieces" to the public. As a strategy intended to develop a new consumerism, while still prioritizing customers' values and their satisfaction, companies have been drawn to this new type of marketing. The current consumption society has converted renowned art pieces from simply works of 'high culture' to a further way of marketing, aimed to differentiate products and dominate the market. Though many products have had masterpieces applied to their designs and have been noticed for their marketability, there has been less systematic research done on the scientific background behind this marketing approach. This research focused on the art pieces' fundamental nature of inducing emotions in the viewer, and hypothesized about how the evaluation of a product may be influenced by the affect provoked by the art piece used. To be more specific, if art pieces with different levels of pleasure and arousal -the two axis of emotion suggested by existing research on emotion -were used on each product, the goal was to see how the different levels influenced the consumer's assessment of the products, focusing on product's type as well as the evaluation of their attributes. First, a pretest was done to verify the relationship between the emotion provoked by the art piece and the consumer's preference. There were two types of surveys, each with five drawings from the ten that were assumed to differ in levels of the two axis of emotion. The survey was composed of questions asking for positive emotion, negative emotion, level of arousal, and preference. The correlation between the measurements of positive and negative emotions was -0.792, so an integrated entry was used in the analysis by subtracting the measurement of negative emotions from that of positive emotions. The first hypothesis that paintings that provoke positive emotions will be more preferred than paintings that bring out negative emotions was supported; and through this research, paintings that were to be used for the products were selected. The second pretest was conducted to settle on an item that would be used in the research. Items meant to measure utilitarian and hedonic attributes of milk and chocolate, the two products to be used in the research, were extracted. Because milk is a utilitarian product with strong practical attributes while chocolate is a hedonic product with strong hedonic attributes, these two were selected to be used in this research. The first study was executed to see if there is a difference in attitude about products that have different painting on their designs, which either induces positive or negative emotions. It was also to verify whether this difference in attitude was mediated by the viewer's preference for the art piece. This study showed that when positive emotion inducing painting was used, the product was better evaluated compared to the product with a painting that provokes a negative emotion, thus supporting the second hypothesis. It was also supported that the effect of affect on product evaluation was mediated by preference for the art piece. The second study was done to see the influence of the level of arousal on the evaluation of the product's attributes. Art pieces that differ in the level of arousal were selected through the pretest, and later it verified the hypothesis that the level of arousal has an effect on the assessment of the attributes of the product. In the case of milk, a utilitarian product, the fourth hypothesis that a high-arousal painting will better evaluated for its hedonic attributes was supported, as well as the fifth, which hypothesized that a low-arousal painting will receive a higher assessment for its utilitarian attributes. However, for chocolate, a hedonic product, both fourth and fifth hypotheses were not supported. This study is significant for the following basis: first, it verified the importance of the emotion induced by the painting on the evaluation of the product's attributes, by applying a systematic and scientific method. Second, it expanded from the existing research on positive/negative emotions to confirm the additional influence of the state of arousal on product evaluation.

  • PDF

A Study on the Artistic Analysis of Modern Commercial Movies (Focusing on "1987(2017)") (현대 상업영화의 예술성 분석연구 (영화 "1987(2017)"을 중심으로))

  • Lee, Tae-Hoon
    • Journal of Digital Convergence
    • /
    • v.16 no.5
    • /
    • pp.425-433
    • /
    • 2018
  • Korea's film industry structure is focused on commercial movies centering on large companies, and its diversity and artistry are relatively overlooked. In addition to trends in the digital media age, the flood of consumable contents on the basis of special effects such as C.G, And is losing popularity as a popular art. The popular art should lead the mature social culture with the educational enlightenment character which induces the indirect experience and the wide insight of the world through the material and expression about the humanities study of the individual and the society. The analysis of the society's artistry and artistry about the movie "(2017)" can be a measure of the definition and kind of artistry in commercial movies and methodology about the manifestation of artistry. As a research methodology, we try to measure the future of the film industry by analyzing the status of the film as popular art, such as intellectual exploration and logical completeness of the essence of society, Through analyzing and criticizing the artistic characteristics in commercial films, I would like to suggest some improvement points by deriving the indicators of the artistic nature of commercial films. The film "1987" is a good example of an ideal commercial film with an artistry that cultivates cultural literacy, promotes civic consciousness through enlightenment messages, and plays a role of self-reflection through art experience. In other words, it shows the possibilities of commercial film with artistry in popular culture, such as a humanistic examination of true history and society, and an introspective gaze of the director expressed through the film society.

Estimation of Relative Economic Weights of Hanwoo Carcass Traits Based on Carcass Market Price

  • Choy, Yun-Ho;Park, Byoung-Ho;Choi, Tae-Jung;Choi, Jae-Gwan;Cho, Kwang-Hyun;Lee, Seung-Soo;Choi, You-Lim;Koh, Kyung-Chul;Kim, Hyo-Sun
    • Asian-Australasian Journal of Animal Sciences
    • /
    • v.25 no.12
    • /
    • pp.1667-1673
    • /
    • 2012
  • The objective of this study was to estimate economic weights of Hanwoo carcass traits that can be used to build economic selection indexes for selection of seedstocks. Data from carcass measures for determining beef yield and quality grades were collected and provided by the Korean Institute for Animal Products Quality Evaluation (KAPE). Out of 1,556,971 records, 476,430 records collected from 13 abattoirs from 2008 to 2010 after deletion of outlying observations were used to estimate relative economic weights of bid price per kg carcass weight on cold carcass weight (CW), eye muscle area (EMA), backfat thickness (BF) and marbling score (MS) and the phenotypic relationships among component traits. Price of carcass tended to increase linearly as yield grades or quality grades, in marginal or in combination, increased. Partial regression coefficients for MS, EMA, BF, and for CW in original scales were +948.5 won/score, +27.3 $won/cm^2$, -95.2 won/mm and +7.3 won/kg when all three sex categories were taken into account. Among four grade determining traits, relative economic weight of MS was the greatest. Variations in partial regression coefficients by sex categories were great but the trends in relative weights for each carcass measures were similar. Relative economic weights of four traits in integer values when standardized measures were fit into covariance model were +4:+1:-1:+1 for MS:EMA:BF:CW. Further research is required to account for the cost of production per unit carcass weight or per unit production under different economic situations.

The Antibiotic Resistance Pattern of Gram-Negative Bacteria in Children Younger Than 24 Months with a Urinary Tract Infection: A Retrospective Single-Center Study over 15 Consecutive Years

  • Lee, Yoon Kyoung;Lee, Haejeong;Kim, Jong Min;Kang, Ji-Man;Lee, Sang Taek;Lee, Nam Yong;Kim, Yae-Jean;Cho, Heeyeon
    • Childhood Kidney Diseases
    • /
    • v.19 no.2
    • /
    • pp.148-153
    • /
    • 2015
  • Purpose: We investigated trends in antibiotic resistance for gram-negative bacteria in infants with a urinary tract infection (UTI) over 15 years at a single institution. Methods: A retrospective chart review was conducted for children younger than 24 months who visited the emergency room and were diagnosed with a UTI between January 2000 and December 2014. We selected urine culture data that grew Escherichia coli and Klebsiella pneumoniae. Baseline clinical information and results of antimicrobial susceptibility tests were analyzed by dividing the 15-year study time frame into three periods (A: 2000-2004, B: 2005-2009, and C: 2010-2014). Results: During the study period, 478 applicable children were identified (E. coli, 89.7% and K. pneumoniae, 10.3%). Antibiotic resistance to third-generation cephalosporins was increased from period A to period C (A, 2.1%; B, 8.3%; C, 8.8%; P=0.025). Resistance to quinolones also showed a steady pattern during periods A to C, although it was not statistically significant (A, 7.9%; B, 9.7%; C, 12.4%; P=0.221). The incidence of Extended-spectrum ${\beta}$-lactamase (ESBL)-producing gram-negative bacteria increased from period A to period C (A, 1.4%; B, 7.6%; C, 8.2%; P=0.012). Conclusion: This study revealed that the common uropathogens E. coli and K. pneumoniae experienced increasing resistance rates against third-generation cephalosporins and a constant antibiotic resistance to quinolones in children younger than 24 months. We also showed a recent increased incidence of ESBL-producing gram-negative bacteria in patients with community-acquired UTIs. Therefore, it is necessary to actively surveil resistance in order to properly select empirical antibiotics.

Multi-step Ahead Link Travel Time Prediction using Data Fusion (데이터융합기술을 활용한 다주기 통행시간예측에 관한 연구)

  • Lee, Young-Ihn;Kim, Sung-Hyun;Yoon, Ji-Hyeon
    • Journal of Korean Society of Transportation
    • /
    • v.23 no.4 s.82
    • /
    • pp.71-79
    • /
    • 2005
  • Existing arterial link travel time estimation methods relying on either aggregate point-based or individual section-based traffic data have their inherent limitations. This paper demonstrates the utility of data fusion for improving arterial link travel time estimation. If the data describe traffic conditions, an operator wants to know whether the situations are going better or worse. In addition, some traffic information providing strategies require predictions of what would be the values of traffic variables during the next time period. In such situations, it is necessary to use a prediction algorithm in order to extract the average trends in traffic data or make short-term predictions of the control variables. In this research. a multi-step ahead prediction algorithm using Data fusion was developed to predict a link travel time. The algorithm performance were tested in terms of performance measures such as MAE (Mean Absolute Error), MARE(mean absolute relative error), RMSE (Root Mean Square Error), EC(equality coefficient). The performance of the proposed algorithm was superior to the current one-step ahead prediction algorithm.