모바일 Deep Residual Network 을 이용한 뎁스 영상 기반 1 인칭 시점 VR 손동작 인식

박혜민 ( Hye Min Park ),박나현 ( Na Hyeon Park ),오지헌 ( Ji Heon Oh ),이철우 ( Cheol Woo Lee ),최형우 ( Hyoung Woo Choi ),김태성 ( Tae-seong Kim ) 한국정보처리학회 2019 한국정보처리학회 학술대회논문집 Vol.26 No.2

가상현실 (Virtual Reality, VR), 증강현실 (Augmented Reality, AR), 혼합현실 (Mixed Reality, MR) 분야에 유용한 인간 컴퓨터 인터페이스 기술은 필수적이다. 특히 휴먼 손동작 인식 기술은 직관적인 상호 작용을 가능하게 하여, 다양한 분야에서 편리한 컨트롤러로 사용할 수 있다. 본 연구에서는 뎁스 영상 기반의 1 인칭 시점 손동작 인식을 위하여 손동작 데이터베이스 생성 시스템을 구축하여, 손 동작 인식기 학습에 필요한 1 인칭 (Egocentric View Point) 데이터베이스를 촬영하여 제작한다. 그리고 모바일 Head Mounted Device(HMD) VR 을 위한 뎁스 영상 기반 1 인칭 시점 손동작 인식 (Hand Pose Recognition, HPR) 딥러닝 Deep Residual Network 를 구현한다. 최종적으로, 안드로이드 모바일 디바이스에 학습된 Residual Network Regressor 를 이식하고 모바일 VR에 실시간 손동작 인식 시스템을 구동하여, 모바일 VR 상 실시간 3D 손동작 인식을 가상 물체와의 상호작용을 통하여 확인 한다.

Distally-extending muscle fibers across involved joints: study of long muscles and tendons of wrist and ankle in late-term fetuses and adult cadavers

Shaohe Wang(Shaohe Wang),Shogo Hayashi(Shogo Hayashi ),Zhe-Wu Jin(Zhe-Wu Jin),Ji Hyun Kim(Ji Hyun Kim),Masahito Yamamoto(Masahito Yamamoto ),Gen Murakami(Gen Murakami ),Shinichi Abe(Shinichi Abe ) 대한해부학회 2023 Anatomy & Cell Biology Vol.56 No.1

It is unclear whether forearm and crural muscle fibers extend distally across the wrist and ankle joints, respectively. We hypothesized, in late-term fetuses, an over-production of muscle bellies extending over the joint. Muscle fibers in histological sections from unilateral wrists and ankles of 16 late-term fetuses (30–40 weeks) were examined and compared with 15 adult cadavers. Muscle fibers of the flexor digitorum profundus (FDP) and flexor digitorum superficialis (FDS) in fetuses, especially muscle bellies to the third and fourth fingers, were found to extend far distally beyond the radiocarpal joint. The extensor digitorum and extensor pollicis longus on the extensor side of the wrist were found to carry distally-extending muscle fibers, but these fibers did not extend beyond the distal end of the radius. In the ankle, most muscle bundles in the flexor hallucis longus (FHL), fibularis brevis (FB) and extensor digitorum longus extended distally beyond the talocrural joint, with most FB muscle fibers reaching the level of the talocalcaneal joint. In adult cadavers, muscle fibers of the FDP and FHL did not reach the levels of the radiocarpal and talocrural joints, respectively, whereas the FB muscle belly always reached the talocalcaneal joint. Similarly, some of the FDS reached the level of the radiocarpal joint. Generally, infants’ movements at the wrist and ankle could result in friction injury to over-extended muscle. However, the calcaneal and FDP tendons might protect the FB and FDS tendons, respectively, from friction stress.

Distal vaginal atresia: a report of a rare type found a late-term fetus and its histological comparison with the normal pelvis

Ji Hyun Kim,Zhe Wu Jin,Hiroshi Abe,Gen Murakami,José Francisco Rodríguez Vázquez,Nobuyuki Hinata 대한해부학회 2022 Anatomy & Cell Biology Vol.55 No.4

Solitary distal vaginal atresia is generally caused by a transverse septum or an imperforate hymen. We found a novel type of distal vaginal atresia in a late-term fetus (gestational age approximately 28 weeks) in our histology collection. This fetus had a vaginal vestibule that was closed and covered by a thick subcutaneous tissue beneath the perineal skin in the immediately inferior or superficial side of the imperforate hymen. The uterus, uterine tube, anus, and anal canal had normal development. The urethral rhabdosphincters were well-developed and had a normal topographical relationship with the vagina, but the urethrovaginal sphincter was absent. Thus, vaginal descent seemed to occur normally and form the vestibule. However, the external orifice of the urethra consisted of a highly folded duct with hypertrophied squamous epithelium. Notably, the corpus cavernosum and crus of the clitoris had poor development and were embedded in the subcutaneous tissue, distant from the vestibule. Normally, the cloacal membrane shifts from the bottom of the urogenital sinus to the inferior aspect of the thick and elongated genital tubercle after establishment of the urorectal septum. Therefore, we speculate there was a failure in the transposition of the cloacal membrane caused by decreased elongation of the genital tubercle. The histology of this anomaly strongly suggested that the hymen does not represent a part of the cloacal membrane, but is instead a product that appears during the late recanalization of the distal vagina after vaginal descent. The transverse septum was also likely to form during this recanalization.

Umbilical cord vessels other than the umbilical arteries and vein: a histological study of midterm human fetuses

Ji Hyun Kim,Shogo Hayashi,Zhe Wu Jin,Gen Murakami,José Francisco Rodríguez Vázquez 대한해부학회 2022 Anatomy & Cell Biology Vol.55 No.4

At birth, the umbilical cord contains various types of thin vessels that are near and outside the umbilicus and separate from the umbilical arteries and vein. These vessels are regarded as the remnant “vitelline vessels” and are often called “umbilical vessels”, although this terminology could lead to confusion with the true umbilical arteries and vein. No study has yet comprehensively examined these vessels using histological sections. Our examination of these vessels in 25 midterm fetuses (gestational age: 10–16 weeks) led to five major findings: (i) all specimens had umbilical branches of the inferior epigastric artery; (ii) 5 specimens had vitelline vein remnants; (iii) 4 specimens had a thin artery originating from the left hepatic artery that ran along the umbilical vein; (iv) 2 specimens had a so-called “para-umbilical vein” that was along the umbilical vein and reached the umbilicus; and (v) all specimens had lymphatic vessels originating from the umbilicus that ran caudally along the umbilical artery. The pelvic vein tributaries were well developed along the intra-abdominal umbilical artery, but did not reach the umbilicus. The lymphatic vessel was distinguished from the veins by an intraluminar cluster of lymphocytes attaching to the endothelium. The arterial branch in the umbilical cord did not accompany veins and lymphatic vessels, in contrast to the mother artery in the rectus abdominis. All these thin vessels seemed to be obliterated when the fibrous umbilical ring grew during late-term. The para-umbilical collateral vein in adults might develop outside the fibrous umbilical ring after birth.

Dense distribution of macrophages in flexor aspects of the hand and foot of mid-term human fetuses

Ji Hyun Kim,Shinichi Abe,Shunichi Shibata,Sachiko Asakawa,Hirotoshi Maki,Gen Murakami,Baik Hwan Cho 대한해부학회 2012 Anatomy & Cell Biology Vol.45 No.4

In the developing human musculoskeletal system, cell death with macrophage accumulation occurs in the thigh muscle and interdigital area. To comprehensively clarify the distribution of macrophages, we immunohistochemically examined 16 pairs of upper and lower extremities without the hip joint (left and right sides) obtained from 8 human fetuses at approximately 10-15 weeks of gestation. Rather than in muscles, CD68-positive macrophages were densely distributed in loose connective tissues of the flexor aspects of the extremities, especially in the wrist, hand and foot. In contrast, no or fewer macrophages were evident in the shoulder and the extensor aspects of the extremities. The macrophages were not concentrated at the enthesis of the tendon and ligament, but tended to be arranged along other connective tissue fibers. Deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick end-labeling revealed apoptosis in the hand lumbricalis muscles, but not in the area of macrophage accumulation. Likewise, podoplanin-positive lymphatic vessels were not localized to areas of macrophage accumulation. Re-organization of the connective tissue along and around the flexor tendons of the hand and foot, such as development of the bursa or tendon sheath at 10-15 weeks, might require the phagocytotic function of macrophages, although details of the mechanism remain unknown.

A marginal branch of the left hepatic artery running along the umbilical vein and supplying the anterior surface of the liver left lobe: a report of 5 cases in 12 Japanese human fetuses

Ji Hyun Kim,Shogo Hayashi,Gen Murakami,José Francisco Rodríguez-Vázquez,Hiroshi Abe 대한해부학회 2023 Anatomy & Cell Biology Vol.56 No.4

In human fetuses, the left hepatic artery (LHA) issues the marginal artery that runs along the umbilical vein and, sometimes, reaches the umbilicus. The further observation demonstrated that, in 5 of 12 Japanese midterm fetuses (crownrump length mm: 46, 50, 54, 59, 102), the marginal artery issued not only a thin umbilical branch but also a liver parenchymal branch that took a posterosuperior recurrent course in a peritoneal fold and supplied the anterior surface of the liver left lobe (segment III). However, in 22 Spanish fetuses of which gestational ages corresponded to the Japanese ones, we did not find the parenchymal branch. Therefore, between human populations, there seemed to be a considerable difference in the incidence as to whether or not the marginal artery issues the liver parenchymal branch. The parenchymal branch might be degenerated at the later stages due to friction between the liver free surface and growing diaphragm.

Percutaneous Sacroplasty for Sacral Metastatic Tumors Under Fluoroscopic Guidance Only

Ji Zhang,Chun-gen Wu,Yi-feng Gu,Ming-hua Li 대한영상의학회 2008 Korean Journal of Radiology Vol.9 No.6

Percutaneous sacroplasty is a safe and effective procedure for sacral insufficient fractures under CT or fluoroscopic guidance; although, few reports exist about sacral metastatic tumors. We designed a pilot study to treat intractable pain caused by a sacral metastatic tumor with sacroplasty. A 62-year-old man and a 38-year-old woman with medically intractable pain due to metastatic tumors of S1 from lymphoma and lung cancer, respectively, underwent percutaneous sacroplasty. Over the course of the follow-up period, the two patients experienced substantial and immediate pain relief that persisted over a 3-month and beyond. The woman had deposition of PMMA (polymethyl methacrylate) in the needle track, but did not experience significant symptoms. No other peri-procedural complications were observed for either patient.

Distribution of CD10-positive epithelial and mesenchymal cells in human mid-term fetuses: a comparison with CD34 expression

Ji Hyun Kim,Si Eun Hwang,Hee Chul Yu,Hong Pil Hwang,Yukio Katori,Gen Murakami,Baik Hwan Cho 대한해부학회 2014 Anatomy & Cell Biology Vol.47 No.1

CD10, a marker of immature B lymphocytes, is expressed in the developing epithelium of mammary glands, hair follicles, and renal tubules of human fetuses. To assess mesenchymal and stromal expression of CD10, we performed immunohistochemical assays in whole body sections from eight fetuses of gestational ages 15-20 weeks. In addition to expression in urinary tract and intestinal epithelium, CD10 was strongly expressed at both gestational ages in fibrous tissues surrounding the airways from the larynx to lung alveoli, in the periosteum and ossification center, and in the glans of external genitalia. CD10 was not expressed, however, in other cavernous tissues. These findings suggest that mesenchymal, in addition to epithelial cells at specific sites, are likely to express CD10. The glomeruli, alveoli, and glans are all end products of budding or outgrowth processes in the epithelium or skin. However, in contrast to the CD34 marker of stromal stem cells, CD10 was not expressed in vascular progenitor cells and in differentiated vascular endothelium. The alternating pattern of CD10 and CD34 expression suggests that these factors play different roles in cellular differentiation and proliferation of the kidneys, airway and external genitalia.

Development and growth of the human fetal sacroiliac joint revisited: a comparison with the temporomandibular joint

Ji Hyun Kim,Zhe Wu Jin,Shogo Hayashi,Gen Murakami,Hiroshi Abe,José Francisco Rodríguez Vázquez 대한해부학회 2023 Anatomy & Cell Biology Vol.56 No.2

The human fetal sacroiliac joint (SIJ) is characterized by unequal development of the paired bones and delayedcavitation. Thus, during the long in utero period, the bony ilium becomes adjacent to the cartilaginous sacrum. This mor­phology may be analogous to that of the temporomandibular joint (TMJ). We examined horizontal histological sections of 24 fetuses at 10–30 weeks and compared the timing and sequences of joint cartilage development, cavitation, and ossification of the ilium. We also examined histological sections of the TMJ and humeroradial joint, because these also contain a disk or disk-like structure. In the ilium, endochondral ossification started in the anterior side of the SIJ, extended posteriorly and reached the joint at 12 weeks GA, and then extended over the joint at 15 weeks GA. Likewise, the joint cartilage appeared at the anterior end of the future SIJ at 12 weeks GA, and extended along the bony ilium posteriorly to cover the entire SIJ at 26 weeks GA. The cavitation started at 15 weeks GA. Therefore, joint cartilage development seemed to follow the ossification of the ilium by extending along the SIJ, and cavitation then occurred. This sequence “ossification, followed by joint cartilage formation, and then cavitation” did not occur in the TMJ or humeroradial joint. The TMJ had a periosteum-like membrane that covered the joint surface, but the humeroradial joint did not. After muscle contraction starts, it is likely that the mechanical stress from the bony ilium induces development of joint cartilage.

Topographical variations of the incisive canal and nasopalatine duct in human fetuses

Ji Hyun Kim,Shunichi Shibata,Hiroshi Abe,Gen Murakami,José Francisco Rodríguez-Vázquez 대한해부학회 2019 Anatomy & Cell Biology Vol.52 No.4

The incisive canal for nerves and vessels is generally thought to run along a suture between the incisive bone (IN) and maxilla. In contrast, there was a report saying the canal passes through the IN or primary palate in human fetuses. Examination of sagittal and frontal sections from 69 fetuses (31 of gestational age [GA] 9–15 weeks and 38 of GA 26–34 weeks) showed that the canal often penetrated the IN at the nasal half of its course and that, in other fetuses, the canal penetrated the IN along its entire course, irrespective of involvement of the nasopalatine duct. Canals developing in and corresponding to parts of the suture resulted in partial enlargement of the thin and tight sutures, which contained loose tissue, vessels, nerves and even a duct. Small processes of the IN were identified as upper irregular parts continuous with inferior main masses of bone in frontal sections but as bone fragments in sagittal sections. In some sections, a thin layer of the maxilla along the canal covered the medial or inferior aspect of the IN. Therefore, the incisive canal with or without duct exhibited a spectrum of variations in topographical relation to the IN-maxillary border. Because the primitive oronasal communication passes through the suture, the nasopalatine duct may have originated from the secondary developed elongation of the nasal epithelium at midterm. A large incisive fossa along the midline on the oral surface of the palate might make a macroscopic finding of variants difficult even in adults.