A study on thermal analysis of MgH2 powder made by hydriding chemical vapor deposition method

Kyungduck Park,한정섭 한국화학공학회 2012 Korean Journal of Chemical Engineering Vol.29 No.10

The desorption kinetics of Mg hydride made by the HCVD method was assessed by thermal analysis in order to study desorption behavior. Desorption kinetics was analyzed by the theoretical equation which was derived on the basis of a continuous moving boundary model. At various initial hydride wt% from 1.65 to 7.42, the sample was heated to 573 K at a rate of 1.0 K/min. The starting temperature of evolution of hydrogen rises higher as the initial hydride wt% increases. The number of thermal desorption peaks corresponds to the occupation sites of hydrogen. As the heating rate was increased, the peak temperatures increased; the peak temperatures for heating rates 1, 2, 3 and 4 K/min were 667, 683, 690 and 698 K, respectively. The pressure range is 0.1 to 0.2 atm for measuring. The activation energy for the decomposition of Mg hydride made by HCVD method was 166 kJ/ mol.

Incidence and Prevalence of Skin Cancers in South Korea from 2008 to 2016: A Nation-Wide Population Based Study

( Kyungduck Park ),( Jung Min Bae ),( Kee Yang Chung ),( Sook Jung Yun ),( Soo Hong Seo ),( Hyo Hyun Ahn ),( Dong-youn Lee ),( Heesu Kim ),( Uri Sohn ),( Byung Cheol Park ) 대한피부과학회 2022 Annals of Dermatology Vol.34 No.2

Background: In South Korea, there have been few nationwide epidemiologic studies about premalignant actinic keratosis (AK), squamous cell carcinoma in situ (Bowen’s disease), nonmelanoma skin cancer (NMSC), malignant melanoma of the skin (MM), Kaposi’s sarcoma (KS), connective and soft tissue cancers, or mycosis fungoides (MF). Objective: Using a nationwide population-based study, we attempted to measure the incidence and the prevalence of the above-mentioned tumors in South Korea. Methods: The database we used included all claims in the Korean National Health Insurance program and the Korean Medical Aid program from 2008 to 2016. The International Classification of Diseases, 10th revision (ICD-10) was used to record diagnoses in this database. This data included AK, Bowen’s disease, NMSC, MM, KS, connective and soft tissue cancers, and MF. Results: The age-standardized incidence and prevalence rate of AK, Bowen’s disease, NMSC, MM, KS, connective and soft tissue cancers, as well as MF increased during the periods we investigated. The incidence and prevalence rate of AK and NMSC have increased two- to three-fold. In the case of Bowen’s disease, MM, KS, connective and soft tissue cancers, or MF, we observed no significant tendency in age-standardized incidence or prevalence. Conclusion: We confirmed that the age-standardized incidence and prevalence rates of NMSC and AK tended to increase. These results might contribute to developing preventive and therapeutic strategies for skin cancers and may become a source for further studies.

비전 AI 기술을 활용한 현장 연계형 디지털 트윈 안전관리 서비스 연구

전지혜(JiHye Jeon),박경덕(Kyungduck Park),윤상병(SangByung Yoon),이지윤(JiYoon Lee) 대한전기학회 2021 정보 및 제어 심포지엄 논문집 Vol.2021 No.10

비전 AI 기술을 활용한 현장 연계형 디지털 트윈 안전관리 서비스 연구

전지혜(JiHye Jeon),박경덕(Kyungduck Park),윤상병(SangByung Yoon),이지윤(JiYoon Lee) 대한전기학회 2021 대한전기학회 학술대회 논문집 Vol.2021 No.10

본 논문에서는 수력 발전 시설의 안전관리 시스템 개발을 위한 비전 AI 분석 기술을 활용한 시설 및 측위 식별, 디지털 트윈 서비스 연계 방안을 제안한다. 수력 시설 현장을 점검하기 위한 모바일 기기의 이미지 센서를 이용하여 점검 대상 시설물을 인식하여 식별하고, 식별 ID를 현재 위치와 매핑하여 실시간 점검자 위치를 판단한다. 모바일 내 빠른 시설 및 측위 식별을 위해서 텐서플로우 프레임워크를 활용하여 추론하였다. 본 기술은 안전관리를 위해 타 센서 등 현장에 추가 설치 없이도 활용 가능함을 보였으며, 디지털 트윈 플랫폼 등 ICT 융합 플랫폼에 추론 데이터가 현장과 연계하여 통합 관리 솔루션으로의 확장 가능성을 보인다.

P288 : Distribution of soil keratinophilic fungi isolated in summer beaches of the south coast in Korea

( Youngil Kim ),( Joon Soo Park ),( Hyunjung Kwon ),( Inyong Kim ),( Insoo Chae ),( Kyungduck Park ),( Hyun Chung ) 대한피부과학회 2014 대한피부과학회 학술발표대회집 Vol.66 No.2

Purpose: Soil keratinophilic fungi are often pathogenic and can harm human. In summer beaches, people are frequently and directly in tough with soil. There are not many studies on the on pathogenic keratinophilic fungi in summer beaches. Objectives: We sought to define the distribution of soil keratinophilic fungi in summer beaches of the south sea in Korea. Methods: Soil samples were collected at 180 sites of 6 different beaches. The beaches are randomly selected regarding the distance. Fungi were isolated by hair baiting technique. Results: 29 strains (16.1%) of keratinophilic fungi were isolated from 180 samples. The most frequent isolated fungus was Microsporum gypseum (72.4%) and followed by Trichophyton ajelloi (13.8%), Microsporum cookei (10.3%), and Chrysosporium (3.4%). The frequency of isolation was highest in shaded dry area (30%). Conclusion: The distribution and species of keratinophilic fungi in south coast of Korea showed different result with previous studies. People should be aware of the pathogenic fungi in summer beaches and prevent the possible superficial fungal infections.

Medical care utilization behavior for treatment of skin diseases: a questionnaire study in dermatologic outpatients of the university hospital

( Hyunjung Kwon ),( Hyungrok Kim ),( Youngil Kim ),( Joonsoo Park ),( Hyun Chung ),( Kyungduck Park ) 대한피부과학회 2015 대한피부과학회 학술발표대회집 Vol.67 No.2

Background: It is important to analyze the medical care utilization behavior and conception of disease treatment of dermatologic patients. However, there have been few studies on the values of this information in Korean literature. Objectives: The aim of this study is to evaluate the medical care utilization behavior and conception of disease treatment of dermatologic outpatients of the university hospital. Methods: A written questionnaire, concerning personal information, treatment behavior, treatment conception, patient satisfaction and patient compliance, was asked to 442 outpatient. Results: Satisfactory outpatient consultation time for dermatology suggested by patients was 14.2 minutes in first-visit consultation, and 9.92 minutes in second-visit consultation. Most patients (76%) sought the dermatologic clinics for dermatoses initially but only 39.8% of patients knew how to distinguish dermatologists. Before visiting the hospital, 52.3% of patients sought disease information, and 28.3% of patients obtained information about doctors in advance. 39.7% of respondents had negative attitude on dermatologic medicine. Conclusion: We advise dermatologists to play a major role in enlightening the patients and constructing proper information system via diversified routes so that we can prevent unreasonable medical care utilization behavior and groundless negative conception in dermatologic treatment.

Investigation of the effects of microampere-ranged alternating current stimulation on the growth of trichophyton rubrum

( Hyungrok Kim ),( Hyunjung Kwon ),( Youngil Kim ),( Kyungduck Park ),( Hyun Chung ),( Joonsoo Park ) 대한피부과학회 2015 대한피부과학회 학술발표대회집 Vol.67 No.2

Background: Fungi are eukaryotic microorganisms including yeast and molds. There have been a lot of researches on modifying the growth of fungi including electric current, mostly fungicidal effect. However microcurrent electric stimulation could stimulate the fungal growth. Objectives: This study aims to investigate the effects of microcurrent electric stimulation on growth of T. rubrum. Methods: Standard sized inoculums of T. rubrum derived from a spore suspension were applied to PDACC plates, which was then gently withdrawn with a sterile pipette and applied to twelve PDACC plates with a sterile spreader. Twelve Petri dishes were divided into 4 groups. The given amperage of electric current was 0.5 レA, 2 レ A, 4 レA in group A, B, C and no electric current was given in group D. Results: In the firth 48 hours, only 500nA and 2レA exposed fungus appeared colonies, which of 500nA were denser. 4レA exposed plates showed a barely visible film of fungus after 96 hours of incubation. Fungal growth became visible after 144 hours in the control group. Conclusion: The lower intensity of electric current was supplied, the faster fungal growth was observed in the amperage range used in this study. On the basis of this pilot study, further studies with larger sample size, various fungal species, and various intensities of electric stimulation should be carried out.

Alitretinoin in the treatment of large cell transformed mycosis fungoides

( Hyungrok Kim ),( Osung Kwon ),( Hyunjung Kwon ),( Youngil Kim ),( Kyungduck Park ),( Hyun Chung ),( Joonsoo Park ) 대한피부과학회 2016 대한피부과학회 학술발표대회집 Vol.68 No.1

Alitretinoin is an endogenous panagonist known to bind all recognized retinoid receptors (RAR/RXR) mediating antiproliferative along with immune-modulating proaptotic effects. Recently, a number of cases have been reported indicating the efficacy of alitretinoin in treating mycosis fungoides. A 47-year-old man presented with a history of intractable pigmented and brownish patches and plaques on whole body for 4 years. The patient had undergone gastrectomy in 2011 due to pervious gastric cancer and has not recurred since the surgery. The histopathology revealed epidermotropism with Pautrier``s microabscess and large cell transformation was observed with CD30 (+) on immunohistochemical analysis. Based on these clinical and histopathological results, the patient was diagnosed with large cell transformed mycosis fungoides. The skin lesion was intractable and had aggravated to an ulcerative form despite treatment such as topical steroids, UBV phototherapy and Methotrexate. Alitretinoin was then administered in combination with UBV phototherapy and topical steroid. After two months, the patient showed significant improvement on the skin lesion with only few brownish hyperpigmented patches left. Herein, we report a rare case of large cell transformed mycosis fungoides successfully treated with alitretinoin.

Unilaterally Presenting Norwegian Scabies Burrows in a Hemiplegic Patient

( Hyungrok Kim ),( Osung Kwon ),( Hyunjung Kwon ),( Youngil Kim ),( Joonsoo Park ),( Hyun Chung ),( Kyungduck Park ) 대한피부과학회 2016 대한피부과학회 학술발표대회집 Vol.68 No.1

Norwegian scabies is a rare, severe form of scabies, often seen in physically or mentally handicapped, immunocompromised, and institutionalized persons. The characteristic skin lesions in this form are gross scaling and hyperkeratotic plaque usually in symmetric distribution. A 55-year-old man presented with generalized pruritic rash. Physical examination revealed scaly erythematous patch with severe crust on his left arm and hand. In contrast, the right hand and arm showed erythematous patches with mildly crusted lesions. The trunk and limbs showed an asymmetrical non-specific rash composed of excoriations and eczematous change, with focal crusting. He suffered from long-standing right hemiplegia with no right hand function. There was no reported case of scabies patient or contact of that matter within the hospital. A scabies mite was seen in KOH examination from the left forearm. The biopsy section from his left forearm showed marked hyperkeratosis and epidermal acanthosis with numerous mites within the stratum corneum. This case is remarkable due to the asymmetric distribution of the burrows, which covered dominantly on the non-paralytic side of the arm. This atypical asymmetric distribution is due to minimal irritation on the non-paralytic side where the mites are left undisturbed for maximal reproduction. Herein, we report a case of asymmetrical Norwegian scabies burrows in a hemiplegic patient.

A case of herpes zoster after physical trauma

( Hyungrok Kim ),( Hyunjung Kwon ),( Youngil Kim ),( Inyong Kim ),( Kyungduck Park ),( Joonsoo Park ),( Hyun Chung ) 대한피부과학회 2015 대한피부과학회 학술발표대회집 Vol.67 No.1

Herpes zoster is a viral disease caused by reactivation of varicella zoster virus(VZV) associated with advanced age, predisposing diseases, immunodeficiency, and mechanicaltrauma. The early diagnosis and prompt treatment of zoster-related symptoms with antiviral treatment or anti-neuropathic medications will have better outcomes and less sequelae. However, the zoster associated neuropathic pain on the traumatic site is often masked with nociceptive pain of tissue injury. A 61-year-old woman presented with erythematous patches and papules on her buttock for a week. It had been developed after slipping down and she complained of severe stabbing nature pain around the lesion. Physical examination revealed 5cm x 2.5cm sized coccygeal hemorrhagic bullae with multiple small vesicles around it. As there was an evidence of coccxygeal fracture on the radiological examination, she first thought that it was a post-traumatic complication such as friction blister. However, histopathological study showed multinucleated keratinocytes, intraepidermal vesicles, epidermal necrosis with ballooning degeneration and intranuclear inclusions, characteristic and confirmatory of an infection with VZV. Based on these clinical and histopathologic findings, she was diagnosed with herpes zoster occurring in S2 dermatome. Herein, we report this case as the proper treatment may be delayed when the zoster patient has a history of trauma on the affected skin lesion.