일부 흡연 대학생의 지각된 스트레스와 흡연실태에 대한 상관관계 연구

강초록,권시내,권혜림,박수경,송인혜,오해인,이미지,한승아,황선아,김수지 이화여자대학교 간호과학대학 2003 이화간호학회지 Vol.- No.37

In spite of the seriousness of smoking harm has been developed these days. the increase of national smoking rate and that the people in the twenties are especially leading the rise of national smoking rate is an important issue of national health. Smoking of the university students can occur health problem and cause loss of manpower and expenses in their social activity period. So then the actual state for prevention of smoking and development of a program to prohibit smoking has to be seized urgently and starting with the study of the realities of university students, the effort to find a related fluent of smoking has to be studied. Related to this, the purpose of this study is to seize the general characteristics of smoking university students and to find out the relationship between perceived stress and smoking status among smoking university students. In addition, by collating the relationship between perceived stress and smoking status among smoking university students we have the purpose to furnish the basal data of stress care, the best way to cope with stress through group training and the plan for nursing implementation to decrease the smoking rate. For this study, a survey was conducted for 204 smoking university students of 13 universities in Seoul from 9th of May to 16th of May, 2003. The collected data was analyzed by t-test, Pearson Correlation and ANOVA in the statistical packages SPSS/PC. Major findings of this study are as follows; 1. Of the 204 respondents 85.4% of them were male and 14.6% of them were female. The average age of the sample was 23.19 years old and 41.8% of them were in senior, 21.4% in junior, 16.9% in sophomore, 19.9% in freshman grade. The major motivation to start smoking was 'because of curiosity'(33.8%) and the first smoking experience was at 'senior high school' (41.9%) and at 'college' (41.9%). 2 The highest scored stress factor of smoking university students were stresses about school work. 3. 72.7% had experience to quit smoking at least one or more times. Most of the reason to keep on smoking was 'short will to quit'(51.0%) and the smoking place was usually at 'school' (41.4%). Most respondents for the number ofsmoking friends were '5 people and above' (73.2%). 4. There was a negative relationship between the general characteristics and the entire perceived stress, however, there was a positive relationship between the general characteristics and the perceived stress in 4 categories which is 'sex distinction', 'major of study', 'residence form' and' inmate'. 5. There was a negative relationship between the general characteristics and the entire smoking status, however, there was a positive relationship between the general characteristics and the smoking status in 2 categories which is 'presence of hobby' and 'number of smoking friends'. 6. There was a negative relationship between the perceived stress and the smoking status. Through this study we have seized the relationship between the general characteristics, perceived stress and the smoking status of smoking university students. There was a positive relationship between some of the general characteristics with the perceived stress and the smoking status of smoking university students. Also there was a negative relationship between the perceived stress and the smoking status.

각이등분법 및 평행법에 의한 전악구내 표준 촬영시 두경부 피부 흡수선량 비교

유명진,김현자,도시홍,나경수,김애지 大韓口腔顎顔面 放射線學會 1990 Imaging Science in Dentistry Vol.20 No.2

This study was performed to measure the skin absorbed doses from full mouth standard intraoral radiography(14 exposures) in bisecting angle and paralleling techniques. Thermoluminescent dosimeters were used in a phantom. Circular tube collimator(60mm in diameter, 20cm in length) and rectangular collimator(35mmX44mm, 40cm in length) were set for bisecting angle and paralleling techniques respectively. All measurement sites were classified into 8 groups according to distance from each point of central rays. The results were as follows: 1. The skin absorbed doses from the paralleling technique were significantly decreased than those from the bisecting technique in both points at central ray and points away from central ray. The percentage rates of decrease were greater at points away from central ray than those at central ray. 2. The skin absorbed doses at the lens of eye, parotid gland, submandibular gland and thyroid region were significantly decreased in paralleling techniuqe, but those of the midline of palate remained similar in both techniques. 3. The highest doses were measured at the site 20mm above the point of central ray for the mandibular premolars in bisecting angle technique and at the point of central ray for the mandibular premolars in paralleling techniques. The lowest doses were measured at the thyroid region in both techniques.

Combining Model-based and Heuristic Techniques for Fast Tracking the Global Maximum Power Point of a Photovoltaic String

Shi, Ji-Ying,Xue, Fei,Ling, Le-Tao,Li, Xiao-Fei,Qin, Zi-Jian,Li, Ya-Jing,Yang, Ting The Korean Institute of Power Electronics 2017 JOURNAL OF POWER ELECTRONICS Vol.17 No.2

Under partial shading conditions (PSCs), multiple maximums may be exhibited on the P-U curve of string inverter photovoltaic (PV) systems. Under such conditions, heuristic methods are invalid for extracting a global maximum power point (GMPP); intelligent algorithms are time-consuming; and model-based methods are complex and costly. To overcome these shortcomings, a novel hybrid MPPT (MPF-IP&O) based on a model-based peak forecasting (MPF) method and an improved perturbation and observation (IP&O) method is proposed. The MPF considers the influence of temperature and does not require solar radiation measurements. In addition, it can forecast all of the peak values of the PV string without complex computation under PSCs, and it can determine the candidate GMPP after a comparison. Hence, the MPF narrows the searching range tremendously and accelerates the convergence to the GMPP. Additionally, the IP&O with a successive approximation strategy searches for the real GMPP in the neighborhood of the candidate one, which can significantly enhance the tracking efficiency. Finally, simulation and experiment results show that the proposed method has a higher tracking speed and accuracy than the perturbation and observation (P&O) and particle swarm optimization (PSO) methods under PSCs.

Transcription changes of a putative trehalose-6-phosphate synthase gene in response to hormone stimulation in Leptinotarsa decemlineata (Say)

Ji-Feng Shi,Qing-Yu Xu,Wen-Chao Guo,Guo-Qing Li 한국응용곤충학회 2016 Journal of Asia-Pacific Entomology Vol.19 No.3

Trehalosemetabolism is critical for production of ATP, provision of carbon source, and facilitation of carbohydrate absorption. Trehalose-6-phosphate synthase (TPS) is a rate-limiting enzyme in trehalose biosynthesis. In the present paper, a TPS gene (LdTPS)was cloned inLeptinotarsa decemlineata. At young larval instars, the expression levels of LdTPS were high just before and right after ecdysis, and were low at the mid instar stages. In the fourthinstar larvae, two peaks occurred at 24 h after ecdysis and at the wandering stage. In vitro midgut culture and an in vivo bioassay revealed that 20E stimulated LdTPS transcription. Conversely, a reduction of 20E by RNA interference (RNAi) of a prothoracicotropic hormone receptor gene LdTorso and an ecdysteroidogenesis gene LdSHD repressed LdTPS expression. Moreover, disruption of 20E signaling by knockdown of LdEcR, LdE75 and LdFTZ-F1 reduced LdTPS transcript levels. Similarly, in vitro culture and an in vivo bioassay showed that exogenous JH or JH analog methoprene and pyriproxyfen activated LdTPS expression. An increase in endogenous JH by RNAi of an allatostatin gene LdAS-C enhanced the transcription. In contrast, a decrease in JH by silencing of a JH biosynthesis gene LdJHAMT downregulated LdTPS expression. Moreover, knockdown of LdILP2 repressed LdTPS transcription. Therefore, LdTPS transcription is tuned by 20E, JH and ILP signaling pathways in L. decemlineata.

Moth-Flame Optimization-Based Maximum Power Point Tracking for Photovoltaic Systems Under Partial Shading Conditions

Shi, Ji-Ying,Zhang, Deng-Yu,Xue, Fei,Li, Ya-Jing,Qiao, Wen,Yang, Wen-Jing,Xu, Yi-Ming,Yang, Ting The Korean Institute of Power Electronics 2019 JOURNAL OF POWER ELECTRONICS Vol.19 No.5

This paper presents a moth-flame optimization (MFO)-based maximum power point tracking (MPPT) method for photovoltaic (PV) systems. The MFO algorithm is a new optimization method that exhibits satisfactory performance in terms of exploration, exploitation, local optima avoidance, and convergence. Therefore, the MFO algorithm is quite suitable for solving multiple peaks of PV systems under partial shading conditions (PSCs). The proposed MFO-MPPT is compared with four MPPT algorithms, namely the perturb and observe (P&O)-MPPT, incremental conductance (INC)-MPPT, particle swarm optimization (PSO)-MPPT and whale optimization algorithm (WOA)-MPPT. Simulation and experiment results demonstrate that the proposed algorithm can extract the global maximum power point (MPP) with greater tracking speed and accuracy under various conditions.

The activation of NLRP3 inflammasome potentiates the immunomodulatory abilities of mesenchymal stem cells in a murine colitis model

( Ji-su Ahn ),( Yoojin Seo ),( Su-jeong Oh ),( Ji Won Yang ),( Ye Young Shin ),( Byung-chul Lee ),( Kyung-sun Kang ),( Eui-suk Sung ),( Byung-joo Lee ),( Hemn Mohammadpour ),( Jin Hur ),( Tae-hoon Shi 생화학분자생물학회(구 한국생화학분자생물학회) 2020 BMB Reports Vol.53 No.6

Inflammasomes are cytosolic, multiprotein complexes that act at the frontline of the immune responses by recognizing pathogen- or danger-associated molecular patterns or abnormal host molecules. Mesenchymal stem cells (MSCs) have been reported to possess multipotency to differentiate into various cell types and immunoregulatory effects. In this study, we investigated the expression and functional regulation of NLR Family Pyrin Domain Containing 3 (NLRP3) inflammasome in human umbilical cord blood-derived MSCs (hUCB-MSCs). hUCB-MSCs expressed inflammasome components that are necessary for its complex assembly. Interestingly, NLRP3 inflammasome activation suppressed the differentiation of hUCB-MSCs into osteoblasts, which was restored when the expression of adaptor proteins for inflammasome assembly was inhibited. Moreover, the suppressive effects of MSCs on T cell responses and the macrophage activation were augmented in response to NLRP3 activation. In vivo studies using colitic mice revealed that the protective abilities of hUCB-MSCs increased after NLRP3 stimulation. In conclusion, our findings suggest that the NLRP3 inflammasome components are expressed in hUCB-MSCs and its activation can regulate the differentiation capability and the immunomodulatory effects of hUCB-MSCs. [BMB Reports 2020; 53(6): 329-334]

Improved Global Maximum Power Point Tracking for Photovoltaic System via Cuckoo Search under Partial Shaded Conditions

Shi, Ji-Ying,Xue, Fei,Qin, Zi-Jian,Zhang, Wen,Ling, Le-Tao,Yang, Ting The Korean Institute of Power Electronics 2016 JOURNAL OF POWER ELECTRONICS Vol.16 No.1

Conventional maximum power point tracking (MPPT) methods are ineffective under partially shaded conditions because multiple local maximum can be exhibited on power-voltage characteristic curve. This study proposes an improved cuckoo search (ICS) MPPT method after investigating the cuckoo search (CS) algorithm applied in solving multiple MPPT. The algorithm eliminates the random step in the original CS algorithm, and the conception of low-power, high-power, normal and marked zones are introduced. The adaptive step adjustment is also realized according to the different stages of the nest position. This algorithm adopts the large step in low-power and marked zones to reduce search time, and a small step in high-power zone is used to improve search accuracy. Finally, simulation and experiment results indicate that the promoted ICS algorithm can immediately and accurately track the global maximum under partially shaded conditions, and the array output efficiency can be improved.

Active Distribution System Planning Considering Battery Swapping Station for Low-carbon Objective using Immune Binary Firefly Algorithm

Ji-Ying Shi,Ya-Jing Li,Fei Xue,Le-Tao Ling,Wen-An Liu,Da-Ling Yuan,Ting Yang 대한전기학회 2018 Journal of Electrical Engineering & Technology Vol.13 No.2

Active distribution system (ADS) considering distributed generation (DG) and electric vehicle (EV) is an effective way to cut carbon emission and improve system benefits. ADS is an evolving, complex and uncertain system, thus comprehensive model and effective optimization algorithms are needed. Battery swapping station (BSS) for EV service is an essential type of flexible load (FL). This paper establishes ADS planning model considering BSS firstly for the minimization of total cost including feeder investment, operation and maintenance, net loss and carbon tax. Meanwhile, immune binary firefly algorithm (IBFA) is proposed to optimize ADS planning. Firefly algorithm (FA) is a novel intelligent algorithm with simple structure and good convergence. By involving biological immune system into FA, IBFA adjusts antibody population scale to increase diversity and global search capability. To validate proposed algorithm, IBFA is compared with particle swarm optimization (PSO) algorithm on IEEE 39-bus system. The results prove that IBFA performs better than PSO in global search and convergence in ADS planning.

Dual-Algorithm Maximum Power Point Tracking Control Method for Photovoltaic Systems based on Grey Wolf Optimization and Golden-Section Optimization

Shi, Ji-Ying,Zhang, Deng-Yu,Ling, Le-Tao,Xue, Fei,Li, Ya-Jing,Qin, Zi-Jian,Yang, Ting The Korean Institute of Power Electronics 2018 JOURNAL OF POWER ELECTRONICS Vol.18 No.3

This paper presents a dual-algorithm search method (GWO-GSO) combining grey wolf optimization (GWO) and golden-section optimization (GSO) to realize maximum power point tracking (MPPT) for photovoltaic (PV) systems. First, a modified grey wolf optimization (MGWO) is activated for the global search. In conventional GWO, wolf leaders possess the same impact on decision-making. In this paper, the decision weights of wolf leaders are automatically adjusted with hunting progression, which is conducive to accelerating hunting. At the later stage, the algorithm is switched to GSO for the local search, which play a critical role in avoiding unnecessary search and reducing the tracking time. Additionally, a novel restart judgment based on the quasi-slope of the power-voltage curve is introduced to enhance the reliability of MPPT systems. Simulation and experiment results demonstrate that the proposed algorithm can track the global maximum power point (MPP) swiftly and reliably with higher accuracy under various conditions.

Improved Global Maximum Power Point Tracking for Photovoltaic System via Cuckoo Search under Partial Shaded Conditions

Ji-Ying Shi,Fei Xue,Zi-Jian Qin,Wen Zhang,Le-Tao Ling,Ting Yang 전력전자학회 2016 JOURNAL OF POWER ELECTRONICS Vol.16 No.1

Conventional maximum power point tracking (MPPT) methods are ineffective under partially shaded conditions because multiple local maximum can be exhibited on power–voltage characteristic curve. This study proposes an improved cuckoo search (ICS) MPPT method after investigating the cuckoo search (CS) algorithm applied in solving multiple MPPT. The algorithm eliminates the random step in the original CS algorithm, and the conception of low-power, high-power, normal and marked zones are introduced. The adaptive step adjustment is also realized according to the different stages of the nest position. This algorithm adopts the large step in low-power and marked zones to reduce search time, and a small step in high-power zone is used to improve search accuracy. Finally, simulation and experiment results indicate that the promoted ICS algorithm can immediately and accurately track the global maximum under partially shaded conditions, and the array output efficiency can be improved.