석면함유 슬레이트 지붕 물받이 퇴적물 중 석면 섬유 함유율

임지현,한솔민,김현석,신유민,박시은,허정윤,김민영,장봉기 순천향대학교 기초과학연구소 2022 순천향자연과학연구 논문집 Vol.28 No.1,2

This study attempted to determine the degree of asbestos release from the aging slate roof by comparing the asbestos content in the slate roof rain gutter with a colored steel plate (tin plate) over the slate roof. Four slate roof houses located in Haengmok-ri, Asan-si, Chungcheongnam-do, and one house constructed with a colored steel plate on the slate roof were selected to collect the sediment of the roof rain gutter. The asbestos fiber content was calculated by a point counting method using a polarization microscope after pretreatment with conversion treatment and hydrochloric acid treatment. The average asbestos content of the four slate roof rain gutter were 1.89%. However, asbestos was not detected in the Slate covering roof rain gutter, which were constructed on the slate roof. Asbestos fiber content was the highest at 2.89% in the slate roof rain gutter installed in 1976, followed by 2.44% in 1953. From the above results, it is necessary to minimize secondary damage as asbestos fibers released from slate roof houses to the surrounding atmosphere or leaked from slate roofs as rainwater may cause soil pollution and seriously affect residents' health. Although covering with colored steel plates (tin plates) has been shown to prevent the leakage of asbestos fibers to some extent, it is believed that a policy alternative to remove the slate roof as soon as possible is needed to solve the fundamental problem.

사무직 근로자의 수면의 질 및 직무스트레스와 우울과의 관련성

강미나,강수영,권수정,김현주,배재원,이보연,이예진,임의롬,정다영,조한솔 이화여자대학교 간호과학대학 2013 이화간호학회지 Vol.- No.47

Purpose: The purpose of this study was to understand the degree of depression, sleep quality, job stress and their association among office workers. Method: A self-administered questionnaire was distributed to 147 workers employed in 5 big enterprises, and 5 small and medium enterprises from October 21 to November 21, 2012. The questionnaires included socio-demographic and health-related characteristics, job-related characteristics, sleep quality, job stress (KOSS) and depression (CES-D). Result: Among all subjects, 23.1% was in the depression group (21 points and over in the CES-D score). Depressive level was positively correlated with job stress and quality of sleep. The adjusted odd ratio for the effects of sleep quality and job stress on depression significantly increased in the depression group compared to that of the normal group. Multiple regression analysis revealed that the following factors of influence had combined explanatory powers on depression: BMI, life satisfaction, quality of sleep, and job stress. Conclusion: The study revealed that complicated influences were exerted on the level of depression by variable factors, as well as socio-demographic characteristics, health-related characteristics, quality of sleep, and job stress. Specifically, the level of depression was influenced by the quality of sleep and job stress.

생체재료용 타이타늄 합금

김한솔 ( Han Sol Kim ),김경택 ( Kyung Taek Kim ),조규섭 ( Gu Serb Cho ),강황진 ( Hwang Jin Kang ),김교한 ( Kyo Han Kim ),김원용 ( Won Yong Kim ) 대한금속재료학회 ( 구 대한금속학회 ) 2009 재료마당 Vol.22 No.2

생체재료용 Ti 합금에 관한 연구는 Ti-Nb계 합금의 저탄성계수와 초탄성·형상기억특성 향상에 초점을 두고 일본과 우리나라에서 활발히 진행되어 왔다. 이들의 연구결과를 종합해 보면, 저탄성계수와 초탄성·형상기억특성 향상은 모두 β상의 상안정성과 집합조직에 크게 영향을 받는다고 할 수 있다. 현재까지 Ti-Nb계 합금의 탄성계수가 상용의 Ti합금에 비해 월등히 낮은 값을 보이지만 아직까지 인체 뼈에 비해 높은 값을 가지고 있으며, 또한 초탄성·형상기억특성은 Nitinol합금에 비해 절반 정도에 불과하여, 앞으로도 탄성계수 저감과 초탄성·형상기억특성 향상에 대해 개발할 여지가 많이 남아있다. 이와 같은 기계적 특성과 함께 생체골의 동작 특성을 고려한 피로특성 또한 연구개발이 필수적으로 동반되어야 할 부분으로 많은 연구자들의 연구수행을 기대하여 본다. 마지막으로 연구개발 수행합금의 in-vitro 및 in-vivo 시험과 같은 생체적합성에 대한 연구 및 임상분야의 연구도 지속적으로 수행되어야 할 것이다.

단핵구세포주 THP-1의 대식세포로의 분화 및 활성화에서 CO의 억제 효과

김다솔(Da Sol Kim),이미선(Mi Sun Lee),김한솔(Han Sol Kim),이혜윤(Hye Yun Lee),김오윤(Oh Yun Kim),강예린(Ye Rin Kang),손동현(Dong Hyun Sohn),김관회(Koanhoi Kim),박영철(Young Chul Park) 한국생명과학회 2017 생명과학회지 Vol.27 No.2

Carbon monoxide (CO)는 세포 보호의 기능을 가지는 항산화 효소인 heme oxygenase-1 (HO-1)의 대사산물로 세포성장, 아폽토시스, 염증에 대한 억제 효과를 보이는 것으로 보고가 이어지고 있고, 이에 관련된 연구가 활발히 진행되고 있는 실정이다. 본 연구에서는 CO가 단핵구의 대식세포로의 분화 및 그 활성화 과정에 미치는 영향을 인간 단핵구세포주 THP-1을 이용하여 조사하였다. CO-releasing compound인 CORM-2는 phorbol 12-myristate 13-acetate (PMA)로 자극한 THP-1 세포에서 viability와 증식에는 큰 영향을 주지 않았으나 부착능의 뚜렷한 감소를 보였다. 그리고, CORM-2는 대식세포의 막표면 분화 인자인 CD14, CD11b 및 CD18의 발현과 latex beads를 이용한 포식 기능을 현저히 억제하였다. 다음으로, 배양중인 THP-1 세포를 PMA로 6일 동안 대식세포로 분화시킨 후 inflammatory cytokines의 분비와 포식 기능을 조사하였다. CORM-2의 처리는 lipopolysaccaride (LPS)로 자극한 대식세포로부터 분비되는 IL-6와 TNF-α의 분비를 감소시켰다. 또한, 분화된 대식세포에 E. coli (K-12 strain) bioparticles를 이용하여 포식 기능을 측정한 결과 CORM-2를 처리한 세포에서는 현저히 감소되는 경향을 보였다. 이를 종합해 볼 때, CO는 항원 인식과 포식 기능에 관여하는 막단백질의 발현을 저해함으로써 단핵구의 분화과정을 억제하였고, 분화된 대식세포의 inflammatory cytokines의 분비 및 포식 기능을 저해함으로써 활성화 과정도 억제하는 것으로 보인다. Carbon monoxide (CO), a reaction product of cytoprotective enzyme heme oxygenase-1 (HO-1), is a gaseous messenger with anti-proliferative, anti-apoptotic, and anti-inflammatory actions in many cell types. Here, we investigated the role of CO on the process of monocyte differentiation induced by phorbol 12-myristate 13-acetate (PMA) in human monocytic THP-1 cells. CORM-2 (tricarbonyldichlororuthenium (II) dimer, Ru₂Cl₄ (CO)6), a CO-releasing compound, decreased a marked cell adherence with a slight reduction of proliferation in monocytic THP-1 cells treated with PMA. And, CORM-2 significantly inhibited expression of differentiation markers such as CD14, CD11b plus CD18 (macrophage-1 antigen, Mac-1 or complement receptor 3, CR3) and phagocytosis of carboxylate-modified red fluorescent latex beads, in PMA-stimulated THP-1 cells. For the further experiments, differentiation of PMA-treated cells was enhanced after the initial 2 days stimulus by removing the PMA-containing media then incubating the cells in fresh media for a another 4 days. And, we observed the secretion of inflammatory cytokines and phagocytosis in differentiated macrophages. Treatment with CORM-2 significantly abolished the secretion of IL-6, TNF-α and phagocytosis using fluorescence-conjugated E. coli (K-12 strain) bioparticles in lipopolysaccharide (LPS)-stimulated differentiated macrophages. In conclusion, these results suggest that CO inhibits the differentiation of monocytic THP-1 cells as well as the activation of differentiated macrophages.

Germination Characteristics of Triploid Watermelon According to Mixing Ratio of Peat moss, Perlite and Vermiculite

Sol Ji Noh,Taek-Goo Jeong,Young-Sang Kim,Jong-Woo Han,Ik-Jei Kim,Tae-Il Kim 한국원예학회 2017 한국원예학회 학술발표요지 Vol.2017 No.5

Development of TILLING System for Screening of Target Gene in Pepper Mutation Population

Han Sol Kang,Yeong Deuk Jo,Sang Hoon Kim,Se Won Kim,Sun-Young Kim,Sang-woo Lee,Si-Yong Kang 한국원예학회 2017 한국원예학회 학술발표요지 Vol.2017 No.5

Development of an Intelligent Gripper that Determines the Gripping Force According to the Weight of the Object

Han-Sol Kim,Gab-Soon Kim 한국정밀공학회 2023 International Journal of Precision Engineering and Vol.24 No.12

In this paper, we describe the development of a two-finger intelligent gripper that can determine the gripping force according to the weight of an object. The two-finger intelligent gripper features two 3-axis force sensors attached to the gripper plate. When this gripper grips an object, it simultaneously measures the weights Fx, Fy, and Fz in the x, y, and z directions of the object, calculates the weight of the object using this, and determines the force to grip the object according to the calculated weight. When the gripper safely grips an unknown object, it securely grips the object based on the determined gripping force. Structural analysis was performed using software to design the gripper, and a two-finger intelligent gripper was manufactured based on the design, and the manufactured two-finger intelligent gripper was subjected to a characteristic test. As a result, the manufactured two-finger intelligent gripper determined the gripping force according to the weight of the object, and was able to safely grip various objects using it.

5-Axis Robot Design for Loading and Unloading Workpieces

Han-Sol Kim,Gab-Soon Kim 한국정밀공학회 2023 International Journal of Precision Engineering and Vol.24 No.12

In this paper, a 5-axis robot capable of loading and unloading workpieces on an automatic lathe was designed and manufactured. This robot consists of 1 axis of vertical movement, 3 axes of horizontal rotation, and 1 axis of 90° rotation gripper. The height of the gripper is performed by a vertical movement mechanism, the horizontal position is performed by three actuators, and the horizontal and vertical position of the workpiece is performed by a rotating gripper. Rotary gripper is used to feed and eject workpieces into and out of the lathe chuck. In order to control the 5-axis robot, the forward kinematics and inverse kinematics were derived, and simulations were conducted based on the results. Structural analysis was conducted to design the robot, and based on the results, a 5-axis robot was manufactured. A characteristic test was conducted on the fabricated 5-axis robot, and as a result, it was determined that the 5-axis robot could safely load and unload workpieces on an automatic lathe.

Relaxed Stability Condition for Polynomial Fuzzy System: Non-Quadratic Lyapunov Function Approach

Han Sol Kim,Jin Bae Park,Young Hoon Joo 제어로봇시스템학회 2013 제어로봇시스템학회 국제학술대회 논문집 Vol.2013 No.10

In this paper, relaxed stability of polynomial fuzzy system is considered. Proposed relaxed stability condition is based on the non-quadratic Lyapunov function (NQLF). Since the condition that contains the time derivative of the fuzzy weighting function (FWF) cannot be casted into linear matrix inequality (LMI) condition, various researches arbitrarily set the bound of its magnitude. To solve this problem, in this paper, the stability condition is directly calculated without setting the bound of magnitude of the time derivative of the FWF, and the condition is casted into sum-of-square (SOS) condition. Finally, to prove the superiority of proposed method, simulation example is given.

Robust Stabilization Condition for a Polynomial Fuzzy System with Parametric Uncertainties

Han Sol Kim,Jin Bae Park,Young Hoon Joo 제어로봇시스템학회 2012 제어로봇시스템학회 국제학술대회 논문집 Vol.2012 No.10

This paper concerns with the robust stabilization condition for the polynomial fuzzy system with parametric uncertainties. In the existing methods, nonlinear system with parametric uncertainties was modeled to the T-S fuzzy system. However, these methods has problem such as large number of the fuzzy rule. Therefore, this paper uses the polynomial fuzzy modeling method to manipulate the robust stabilization problem for the parameter uncertain nonlinear system. Furthermore, since new robust stabilization condition is derived from the polynomial Lyapunov function, so the condition is less conservative than previous robust stabilization condition. Finally, numerical example is given to show the validity of proposed method.