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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.

Expression of Yippee-Like 5 (YPEL5) Gene During Activation of Human Peripheral T Lymphocytes by Immobilized Anti-CD3 (인체 말초혈액의 활성화 과정 중 yippee-like 5 (YPEL5) 유전자의 발현 양상)

  • Jun, Do-Youn;Park, Hye-Won;Kim, Young-Ho
    • Journal of Life Science
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    • v.17 no.12
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    • pp.1641-1648
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    • 2007
  • Yippee-like proteins, which have been identified as the homolog of Drosophila yippee protein containing a zinc-finger domain, are known to be highly conserved among eukaryotes. However, their functional roles are still poorly understood. Recently we initiated ordered differential display (ODD)-polymerase chain reaction (PCR) to isolate genes of which expressions are altered following activation of human T cells. On the ODD-PCR image, one PCR-product detected in unstimulated T cells was not detectable at the time when the activated T cells traversed near $G_1/S$ boundary following activation by immobilized anti-CD3. Cloning and nucleotide sequence analysis revealed that the PCR-product was yippee-like 5 (YPEL5) gene, which was known as a human homolog of the Drosophila yippee gene. Northern blot analysis confirmed the amount of ${\sim}2.2$ kb YPEL5 mRNA expression detectable in unstimulated T cells was sustained until 1.5 hr after activation and then rapidly declined to undetectable level by 5 hr. Ectopic expression of YPEL5 gene in human cervix epitheloid carcinoma HeLa cells caused a significant reduction in cell proliferation to the level of 47% of the control. Expression of GFP-YPEL5 fusion protein in HeLa cells showed its nuclear localization. These results demonstrated that the expression level of human YPEL5 mRNA was negatively regulated in the early stage of T cell activation, and suggested that YPEL5 might exert an inhibitory effect on the cell proliferation as a nuclear protein.

Personal Information Overload and User Resistance in the Big Data Age (빅데이터 시대의 개인정보 과잉이 사용자 저항에 미치는 영향)

  • Lee, Hwansoo;Lim, Dongwon;Zo, Hangjung
    • Journal of Intelligence and Information Systems
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    • v.19 no.1
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    • pp.125-139
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    • 2013
  • Big data refers to the data that cannot be processes with conventional contemporary data technologies. As smart devices and social network services produces vast amount of data, big data attracts much attention from researchers. There are strong demands form governments and industries for bib data as it can create new values by drawing business insights from data. Since various new technologies to process big data introduced, academic communities also show much interest to the big data domain. A notable advance related to the big data technology has been in various fields. Big data technology makes it possible to access, collect, and save individual's personal data. These technologies enable the analysis of huge amounts of data with lower cost and less time, which is impossible to achieve with traditional methods. It even detects personal information that people do not want to open. Therefore, people using information technology such as the Internet or online services have some level of privacy concerns, and such feelings can hinder continued use of information systems. For example, SNS offers various benefits, but users are sometimes highly exposed to privacy intrusions because they write too much personal information on it. Even though users post their personal information on the Internet by themselves, the data sometimes is not under control of the users. Once the private data is posed on the Internet, it can be transferred to anywhere by a few clicks, and can be abused to create fake identity. In this way, privacy intrusion happens. This study aims to investigate how perceived personal information overload in SNS affects user's risk perception and information privacy concerns. Also, it examines the relationship between the concerns and user resistance behavior. A survey approach and structural equation modeling method are employed for data collection and analysis. This study contributes meaningful insights for academic researchers and policy makers who are planning to develop guidelines for privacy protection. The study shows that information overload on the social network services can bring the significant increase of users' perceived level of privacy risks. In turn, the perceived privacy risks leads to the increased level of privacy concerns. IF privacy concerns increase, it can affect users to from a negative or resistant attitude toward system use. The resistance attitude may lead users to discontinue the use of social network services. Furthermore, information overload is mediated by perceived risks to affect privacy concerns rather than has direct influence on perceived risk. It implies that resistance to the system use can be diminished by reducing perceived risks of users. Given that users' resistant behavior become salient when they have high privacy concerns, the measures to alleviate users' privacy concerns should be conceived. This study makes academic contribution of integrating traditional information overload theory and user resistance theory to investigate perceived privacy concerns in current IS contexts. There is little big data research which examined the technology with empirical and behavioral approach, as the research topic has just emerged. It also makes practical contributions. Information overload connects to the increased level of perceived privacy risks, and discontinued use of the information system. To keep users from departing the system, organizations should develop a system in which private data is controlled and managed with ease. This study suggests that actions to lower the level of perceived risks and privacy concerns should be taken for information systems continuance.

Evaluation of Drainage Improvement Effect Using Geostatistical Analysis in Poorly Drained Sloping Paddy Soil (경사지 배수불량 논에서 배수개선 효과의 지구통계적 기법을 이용한 평가)

  • Jung, Ki-Yuol;Yun, Eul-Soo;Park, Ki-Do;Park, Chang-Young
    • Korean Journal of Soil Science and Fertilizer
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    • v.43 no.6
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    • pp.804-811
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    • 2010
  • The lower portion of sloping paddy fields normally contains excessive moisture and the higher water table caused by the inflow of ground water from the upper part of the field resulting in non-uniform water content distribution. Four drainage methods namely Open Ditch, Vinyl Barrier, Pipe Drainage and Tube Bundle for multiple land use were installed within 1-m position from the lower edge of the upper embankment of sloping alluvial paddy fields. Knowledge of the spatial variability of soil water properties is of primary importance for management of agricultural lands. This study was conducted to evaluate the effect of drainage in the soil on spatial variability of soil water content using the geostatistical analysis. The soil water content was collected by a TDR (Time Domain Reflectometry) sensor after the installation of subsurface drainage on regular square grid of 80 m at 20 m paddy field located at Oesan-ri, Buk-myeon, Changwon-si in alluvial slopping paddy fields ($35^{\circ}22^{\prime}$ N, $128^{\circ}35^{\prime}$). In order to obtain the most accurate field information, the sampling grid was divided 3 m by 3 m unit mesh by four drainage types. The results showed that spatial variance of soil water content by subsurface drainage was reduced, though yield of soybean showed the same trends. Value of "sill" of soil water content with semivariogram was 9.7 in Pipe Drainage, 86.2 in Open Ditch, and 66.8 in Vinyl Barrier and 15.7 in Tube Bundle.

A Study on the Social Venture Startup Phenomenon Using the Grounded Theory Approach (근거이론 접근법을 이용한 소셜벤처 창업 현상에 관한 고찰)

  • Seol, Byung Moon;Kim, Young Lag
    • Asia-Pacific Journal of Business Venturing and Entrepreneurship
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    • v.18 no.1
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    • pp.67-83
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    • 2023
  • The social venture start-up phenomenon is found from the perspectives of social enterprise and for-profit enterprise. This study aims to fundamentally explore the start-up phenomenon of social ventures from these two perspectives. Considering the lack of prior research that researched both social and commercial perspectives at the same time, this paper analyzed using grounded theory approach of Strauss & Corbin(1998), an inductive research method that analyzes based on prior research and interview data. In order to collect data for this study, eight corporate representatives currently operating social ventures were interviewed and data and phenomena were analyzed. This progressed to a theoretical saturation where no additional information was derived. The analysis results of this study using the grounded theory approach are as follows. As a result of open coding and axial coding, 147 concepts and 70 subcategories were derived, and 18 categories were derived through the final abstraction process. In the selective coding, 'expansion of social venture entry in the social domain' and 'expansion of social function of for-profit companies' were selected as key categories, and a story line was formed around this. In this study, we saw that it is necessary to conduct academic research and analysis on the competitive factors required for companies that pursue the values of two conflicting relationships, such as social ventures, to survive with competitiveness. In practice, concepts such as collaboration with for-profit companies, value combination, entrepreneurship competency and performance improvement, social value execution competency reinforcement, communication strategy, for-profit enterprise value investment, and entrepreneur management competency were derived. This study explains the social venture phenomenon for social enterprises, commercial enterprises, and entrepreneurs who want to enter the social venture field. It is expected to provide the implications necessary for successful social venture startups.

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Effects of Baicalin on Gene Expression Profiles during Adipogenesis of 3T3-L1 Cells (3T3-L1 세포의 지방세포형성과정에서 Baicalin에 의한 유전자 발현 프로파일 분석)

  • Lee, Hae-Yong;Kang, Ryun-Hwa;Chung, Sang-In;Cho, Soo-Hyun;Yoon, Yoo-Sik
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.39 no.1
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    • pp.54-63
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    • 2010
  • Baicalin, a flavonoid, was shown to have diverse effects such as anti-inflammatory, anti-cancer, anti-viral, anti-bacterial and others. Recently, we found that the baicalin inhibits adipogenesis through the modulations of anti-adipogenic and pro-adipogenic factors of the adipogenesis pathway. In the present study, we further characterized the molecular mechanism of the anti-adipogenic effect of baicalin using microarray technology. Microarray analyses were conducted to analyze the gene expression profiles during the differentiation time course (0 day, 2 day, 4 day and 7 day) in 3T3-L1 cells with or without baicalin treatment. We identified a total of 3972 genes of which expressions were changed more than 2 fold. These 3972 genes were further analyzed using hierarchical clustering analysis, resulting in 20 clusters. Four clusters among 20 showed clearly up-regulated expression patterns (cluster 8 and cluster 10) or clearly down-regulated expression patterns (cluster 12 and cluster 14) by baicalin treatment for over-all differentiation period. The cluster 8 and cluster 10 included many genes which enhance cell proliferation or inhibit adipogenesis. On the other hand, the cluster 12 and cluster 14 included many genes which are related with proliferation inhibition, cell cycle arrest, cell growth suppression or adipogenesis induction. In conclusion, these data provide detailed information on the molecular mechanism of baicalin-induced inhibition of adipogenesis.

Balance of Power and the Relative Military Capacity - Empirical Analysis and Implication to North East Asia - (세력균형(power balance)에서의 군사력 수준과 동북아시아에 주는 함의)

  • Kim, Myung-soo
    • Strategy21
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    • s.38
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    • pp.112-162
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    • 2015
  • This study began to confirm or review the balance of power theory by applying scientific methods through experiential cases. Though there are several kinds of national power, this study supposes military power as a crucial power when it comes to war and peace. This research covered balance and imbalance through comparing relative military power between nations or nations' group. Comparison of relative military power can be achieved by statistically processing the values of which has been converted into the standard variables in same domain, then calculating the values of nation's power which has been synthesized different experiential factors. In addition, the criteria of experiential experiment is highly dedicated to European countries, USA, Japan prior to 1st and 2nd World War, as well as USA, Soviet Union and North East Asia during Cold War era. In addition, the balance of power theory has been redefined to review the action of the state upon the changes of power as mentioned in the theory. To begin with, the redefined theory states that relative level of military power between nations defines the consistency of peace and balance of power. If military power is enough to be on the range of level required to keep the power in equilibrium, peace and balance can be achieved. The opposite would unbalance the military power, causing conflicts. While the relative military level between nations change, nations seek to establish 'nations group' via military cooperation such as alliance, which also shift relative military power between nations group as well. Thus, in order to achieve balance of power, a nation seeks to strengthen its military power(self-help), while pursuing military cooperation(or alliance). This changes relative military power between nations group also. In other words, if there exists balance of power between nations, there is balance of power between nations group as well. In this theory, WWI and II broke out due to the imbalance of military force between nations and nations group, and reviewed that due to the balance of military force during the Cold War, peace was maintained. WWI was resulted from imbalance of military cooperation between two powerful states group and WWII was occurred because of the imbalance among the states. Peace was maintained from cooperation of military power and balance among the states during the Cold War. Imbalance among continental states is more threatening than maritime states and balance of power made by army force and naval force also is feasible. Also the outcomes of two variables are found military power balanced ratio of military power for balance is 67% when variable ratio of balance is 100% and standard value for balance is 0.86. Military power exists in a form of range. The range is what unstabilized the international system causing nations to supplement their military powers. These results made possible the calculation and comparison between state's military power. How balance of power inflicted war and peace has been studied through scientific reviews. Military conflict is highly possible upon already unbalanced military powers of North East Asian countries, if the US draws its power back to America. China and Japan are constantly building up their military force. On the other hand, Korean military force is inferior so in accordance to change of international situation state's survival could be threatened and it is difficult to achieve drastic increase in military force like Germany did. Especially constructing naval force demands lots of time; however but has benefit that naval force can overcome imbalance between continental states and maritime states.

Review of 2011 Major Medical Decisions (2011년 주요 의료 판결 분석)

  • Yoo, Hyun-Jung;Seo, Young-Hyun;Lee, Jung-Sun;Lee, Dong-Pil
    • The Korean Society of Law and Medicine
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    • v.13 no.1
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    • pp.199-247
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    • 2012
  • According to the review and analysis of medical cases that are assigned to the Supreme Court and all local High Court in 2011 and that are presented in the media, it was found that the following categories were taken seriously, medical and pharmaceutical product liability, the third principle of trust between medical institutions, negligence and causation estimation, responsibility limit, the meaning of medical records and related judgment of disturbed substantiation, Oriental doctors' duties to explain the procedures, IMS events, whether one can claim for each medical care operated by non-physician health care institutions to the nonmedical domain in the National Health Insurance Corporation, and the basis of norms for each claim. In the cases related to medical pharmaceutical product liability, Supreme Court alleviated burden of proof for accidents with medical and pharmaceutical products prior to the practice of Product Liability Law and onset the point of negative prescription as the time of damage strikes to condition feasibility of the specific situation. In the cases related to the 3rd principle of trust between medical institutions, the Supreme Court refused to sentence the doctor who has trusted the judgment of the same third-party doctors the violations of the care duty. With respect to proof of a causal relationship and damages in a medical negligence case, the Supreme Court decided that it is unjust to deny negligence by the materials of causal relationship rejecting the original verdict and clarified that the causal relationship shall not deny the reasons to limit doctors' responsibilities. In order not put burden on patients with disadvantages in which medical records and the description of the practice or the most fundamental and important evidence to prove negligence and causation are being neglected, the Supreme Court admitted in the hospital's responsibility for the case of the neonate death of suffocation without properly listed fetal heart rate and uterine contraction monitor. On the other hand, the Seoul Western District Court has admitted alimony for altering and forging medical records. With respect to doctors' obligations to description, the Supreme Court decided that it is necessary to explain the foreseen risks by the combination of oriental and western medicines emphasizing the right of patient's self-determination. However, questions have arisen whether it is realistically feasible or not. In a case of an unlicensed doctor performing intramuscular stimulation treatment (IMS), the Supreme Court put off its decision if it was an unlicensed medical practice as to put limitation of eastern and western medical practices, but it declared that IMS practice was an acupuncture treatment therefore the plaintiff's conduct being an illegal act. In the future, clear judgment on this matter should be made. With respect to the claim of bills from non-physical health care institutions, the Supreme Court decided to void it for the implementation of the arrangement is contrary to the commitments made in the medical law and therefore, it is invalid to claim. In addition, contrast to the private healthcare professionals, who are subject to redemption according to the National Healthcare Insurance Law, the Seoul High Court explicitly confirmed that the non-professionals who receive the tort operating profit must return the unjust enrichment and have the liability for damages. As mentioned above, a relatively wide range of topics were discussed in medical field of 2011. In Korea's health care environment undergoing complex changes day by day, it is expected to see more diverse and in-depth discussions striding out to the development in the field of health care.

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Long-term Effects of Change in Family Structure On Achievement During Transition to Adulthood : Focusing on the effect of parental divorce/death on health condition, depression and educational attainment (가족구조의 변화가 성인이행기 발달에 미치는 영향 : 주관적 건강상태, 우울, 교육성취를 중심으로)

  • Kim, Yeonwoo
    • Korean Journal of Social Welfare Studies
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    • v.41 no.4
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    • pp.225-246
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    • 2010
  • The family environment children are exposed to growing up greatly influences their future potential and achievements. Previous findings show that changes in family structure during childhood, particularly those resulting from divorce or death, cause lasting negative consequence that affect the child physically, psychologically, economically, and socially. Unfortunately, single-parent households are becoming increasingly common in Korea, nearly doubling to more than a million cases in the last two decades. Existing domestic and international studies of this area tend to focus on the short-term effects of growing up in a single-parent household. In addition, these studies group their samples in ways that result in findings that may be too broad or are not necessarily an accurate representation of the subjects. This study attempts to address some of these shortcomings by focusing on the long-term effects of how changes in family structure early in children's lives affect achievement during their transition to adulthood. In addition, it takes into account the development cycle the child is in at the time of family restructuring, and what kind of long-term effects result from that. In this analysis, we find that there are several cases of statistically significantly differences in domain achievement depending on the developmental stage the child was in when the parental divorce or death occurred. The findings indicate that changes in family structure during the infant/toddler period influence health condition and depression, while changes in family structure during middle-childhood and adolescence do not. Meanwhile, changes in family structure during any point in the developmental stages have negative effects on educational attainment, with the severity of these negative effects depending on when the family changes occur. The negative effect on educational attainment is most prominent when a change in family structure occurs during the infant/toddler period, followed by adolescence, then middle-childhood.

Deep Learning-based Fracture Mode Determination in Composite Laminates (복합 적층판의 딥러닝 기반 파괴 모드 결정)

  • Muhammad Muzammil Azad;Atta Ur Rehman Shah;M.N. Prabhakar;Heung Soo Kim
    • Journal of the Computational Structural Engineering Institute of Korea
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    • v.37 no.4
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    • pp.225-232
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    • 2024
  • This study focuses on the determination of the fracture mode in composite laminates using deep learning. With the increase in the use of laminated composites in numerous engineering applications, the insurance of their integrity and performance is of paramount importance. However, owing to the complex nature of these materials, the identification of fracture modes is often a tedious and time-consuming task that requires critical domain knowledge. Therefore, to alleviate these issues, this study aims to utilize modern artificial intelligence technology to automate the fractographic analysis of laminated composites. To accomplish this goal, scanning electron microscopy (SEM) images of fractured tensile test specimens are obtained from laminated composites to showcase various fracture modes. These SEM images are then categorized based on numerous fracture modes, including fiber breakage, fiber pull-out, mix-mode fracture, matrix brittle fracture, and matrix ductile fracture. Next, the collective data for all classes are divided into train, test, and validation datasets. Two state-of-the-art, deep learning-based pre-trained models, namely, DenseNet and GoogleNet, are trained to learn the discriminative features for each fracture mode. The DenseNet models shows training and testing accuracies of 94.01% and 75.49%, respectively, whereas those of the GoogleNet model are 84.55% and 54.48%, respectively. The trained deep learning models are then validated on unseen validation datasets. This validation demonstrates that the DenseNet model, owing to its deeper architecture, can extract high-quality features, resulting in 84.44% validation accuracy. This value is 36.84% higher than that of the GoogleNet model. Hence, these results affirm that the DenseNet model is effective in performing fractographic analyses of laminated composites by predicting fracture modes with high precision.