Hiroharu Kawanaka

Dr. Hiroharu Kawanaka

orcid

Research Focus & Metrics

Academic Career Length

24Years (2003-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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25 June 2018 in Biomedical Engineering Letters
Verified
Journal Article
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AYAsami Yonekura
Asami Yonekura
HKHiroharu Kawanaka
Hiroharu Kawanaka
V. B. Surya PrasathV. B. Surya Prasath
V. B. Surya Prasath
Bruce AronowBruce Aronow
Bruce Aronow
HTHaruhiko Takase
Haruhiko Takase

21 July 2024 in Computers in Biology and Medicine
Verified
Journal Article
Open access
RNRiku Nakagaki
Riku Nakagaki
SDShyam Sundar Debsarkar
Shyam Sundar Debsarkar
HKHiroharu Kawanaka
Hiroharu Kawanaka
Bruce AronowBruce Aronow
Bruce Aronow
V. B. Surya PrasathV. B. Surya Prasath
V. B. Surya Prasath
In the field of histopathology, many studies on the classification of whole slide images (WSIs) using artificial intelligence (AI) technology have been reported. We have studied the disease progression assessment of glioma. Adult-type diffuse gliomas, a type of brain tumor, are classified into astrocytoma, oligodendroglioma, and glioblastoma. Astrocytoma and oligodendroglioma are also called low grade glioma (LGG), and glioblastoma is also called glioblastoma multiforme (GBM). LGG patients frequently have isocitrate dehydrogenase (IDH) mutations. Patients with IDH mutations have been reported to have a better prognosis than patients without IDH mutations. Therefore, IDH mutations are an essential indicator for the classification of glioma. That is why we focused on the IDH1 mutation. In this paper, we aimed to classify the presence or absence of the IDH1 mutation using WSIs and clinical data of glioma patients. Ensemble learning between the WSIs model and the clinical data model is used to classify the presence or absence of IDH1 mutation. By using slide level labels, we combined patch-based imaging information from hematoxylin and eosin (H & E) stained WSIs, along with clinical data using deep image feature extraction and machine learning classifier for predicting IDH1 gene mutation prediction versus wild-type across cohort of 546 patients. We experimented with different deep learning (DL) models including attention-based multiple instance learning (ABMIL) models on imaging data along with gradient boosting machine (LightGBM) for the clinical variables. Further, we used hyperparameter optimization to find the best overall model in terms of classification accuracy. We obtained the highest area under the curve (AUC) of 0.823 for WSIs, 0.782 for clinical data, and 0.852 for ensemble results using MaxViT and LightGBM combination, respectively. Our experimental results indicate that the overall accuracy of the AI models can be improved by using both clinical data and images.

1 July 2020 in IEEE/CAA Journal of Automatica Sinica
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Journal Article
Closed access
CPChinthaka Premachandra
Chinthaka Premachandra
Dang Ngoc Hoang ThanhDang Ngoc Hoang Thanh
Dang Ngoc Hoang Thanh
TKTomotaka Kimura
Tomotaka Kimura
HKHiroharu Kawanaka
Hiroharu Kawanaka

19 May 2016 in Journal of Advanced Computational Intelligence and Intelligent Informatics
Verified
Journal Article
Open access
PSPakizar Shamoi
Pakizar Shamoi
AIAtsushi Inoue
Atsushi Inoue
HKHiroharu Kawanaka
Hiroharu Kawanaka
In this paper, we propose a novel approach toward the development of a perceptual color space, FHSI, which stands for “Fuzzy HSI," because it is based on the fuzzification of the well-known HSI color space. FHSI represents a set of fuzzy colors obtained by partitioning the gamut of feasible colors in the HSI model corresponding to standardized linguistic tags. In fact, color categorization was performed on the basis of personal judgments of humans collected by way of an online survey. This approach helps to significantly enhance color matching and similarity searches by producing more intuitive and human-consistent output for users. The introduced method has potential for use in various color image applications involving query processing, for example, in the coordination of online apparel shopping.

1 April 2025 in IEEE Access
Verified
Journal Article
Open access
SSSatoshi Shirae
Satoshi Shirae
SDShyam Sundar Debsarkar
Shyam Sundar Debsarkar
HKHiroharu Kawanaka
Hiroharu Kawanaka
BABruce Aronow
Bruce Aronow
V. B. Surya PrasathV. B. Surya Prasath
V. B. Surya Prasath
Glioma is the most common malignant tumor of the central nervous system, and diffuse Glioma is classified as grades II-IV by world health organization (WHO). In the the cancer genome atlas (TCGA) Glioma dataset, grade II and III Gliomas are classified as low-grade glioma (LGG), and grade IV Gliomas as glioblastoma multiforme (GBM). In clinical practice, the survival and treatment process with Glioma patients depends on properly diagnosing the subtype. With this background, there has been much research on Glioma over the years. Among these researches, the origin and evolution of whole slide images (WSIs) have led to many attempts to support diagnosis by image analysis. On the other hand, due to the disease complexities of Glioma patients, multimodal analysis using various types of data rather than a single data set has been attracting attention. In our proposed method, multiple deep learning models are used to extract features from histopathology images, and the features of the obtained images are concatenated with those of the clinical data in a fusion approach. Then, we perform patch-level classification by machine learning (ML) using the concatenated features. Based on the performances of the deep learning models, we ensemble feature sets from top three models and perform further classifications. In the experiments with our proposed ensemble fusion AI (EFAI) approach using WSIs and clinical data of diffuse Glioma patients on TCGA dataset, the classification accuracy of the proposed multimodal ensemble fusion method is 0.936 with an area under the curve (AUC) value of 0.967 when tested on a balanced dataset of 240 GBM, 240 LGG patients. On an imbalanced dataset of 141 GBM, 242 LGG patients the proposed method obtained the accuracy of 0.936 and AUC of 0.967. Our proposed ensemble fusion approach significantly outperforms the classification using only histopathology images alone with deep learning models. Therefore, our approach can be used to support the diagnosis of Glioma patients and can lead to better diagnosis.

1 April 2021 in Micromachines
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Journal Article
Open access
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STShinya Tokunaga
Shinya Tokunaga
CPChinthaka Premachandra
Chinthaka Premachandra
HPH. Waruna H. Premachandra
H. Waruna H. Premachandra
HKHiroharu Kawanaka
Hiroharu Kawanaka
SSSagara Sumathipala
Sagara Sumathipala
BSB.H. Sudantha
B.H. Sudantha
Several robot-related studies have been conducted in recent years; however, studies on the autonomous travel of small mobile robots in small spaces are lacking. In this study, we investigate the development of autonomous travel for small robots that need to travel and cover the entire smooth surface, such as those employed for cleaning tables or solar panels. We consider an obstacle-available surface and target this travel on it by proposing a spiral motion method. To achieve the spiral motion, we focus on developing autonomous avoidance of obstacles, return to original path, and fall prevention when robots traverse a surface. The development of regular travel by a robot without an encoder is an important feature of this study. The traveled distance was measured using the traveling time. We achieved spiral motion by analyzing the data from multiple small sensors installed on the robot by introducing a new attitude-control method, and we ensured that the robot returned to the original spiral path autonomously after avoiding obstacles and without falling over the edge of the surface.