• Proceedings of the Korean Vacuum Society Conference
• /
• 2011.08a
• /
• pp.53-53
• /
• 2011

This paper describes results for surface and bulk characterization of the most promising thin film solar cell material for high performance devices, (Ag,Cu) (In,Ga) Se2 (ACIGS). This material in particular exhibits a range of exotic behaviors. The surface and general materials science of the material also has direct implications for the operation of solar cells based upon it. Some of the techniques and results described will include scanning probe (AFM, STM, KPFM) measurements of epitaxial films of different surface orientations, photoelectron spectroscopy and inverse photoemission, Auger electron spectroscopy, and more. Bulk measurements are included as support for the surface measurements such as cathodoluminescence imaging around grain boundaries and showing surface recombination effects, and transmission electron microscopy to verify the surface growth behaviors to be equilibrium rather than kinetic phenomena. The results show that the polar close packed surface of CIGS is the lowest energy surface by far. This surface is expected to be reconstructed to eliminate the surface charge. However, the AgInSe2 compound has yielded excellent atomic-resolution images of the surface with no evidence of surface reconstruction. Similar imaging of CuInSe2 has proven more difficult and no atomic resolution images have been obtained, although current imaging tunneling spectroscopy images show electronic structure variations on the atomic scale. A discussion of the reasons why this may be the case is given. The surface composition and grain boundary compositions match the bulk chemistry exactly in as-grow films. However, the deposition of the heterojunction forming the device alters this chemistry, leading to a strongly n-type surface. This also directly explains unpinning of the Fermi level and the operation of the resulting devices when heterojunctions are formed with the CIGS. These results are linked to device performance through simulation of the characteristic operating behaviors of the cells using models developed in my laboratory.

• Journal of Pharmacopuncture
• /
• v.20 no.3
• /
• pp.173-178
• /
• 2017

Objectives: Medicinal plants are vital sources of bioactive compounds that are useful for the treatment of patients with snake bites or are indirectly applicable for boosting the effects of conventional serum therapy. These plants are being used traditionally by local healers and tribes for the treatment of patients with snake bites and therefore can be used as an alternative against snake envenomation. Scientifically, using the secondary metabolites of plants to neutralize venom enzymes has an extra benefit of being based on traditional knowledge; also, the use of such metabolites for the treatment of patients with snake bites is cheaper and the treatment can be started sooner. Methods: All the available information on various secondary metabolites exhibiting venom neutralizing ability were collected via electronic search (using Google books, Pubmed, SciFinder, Scirus, Google Scholar, and Web of Science) and articles of peer-reviewed journals. Results:Recent interest in different plant has focused on isolating and identifying of different phytoconstituents that exhibit Phospholipase A2 activity and other venom enzyme neutralizing ability. In this support convincing evidence in experimental animal models are available. Conclusion: Secondary metabolites are naturally present, have no side effect, are stable for a long time, can be easily stored, and can neutralize a wide range of snake enzymes, such as phospholipase A2, hyaluronidase, protease, L-amino acid oxidase, 5'nucleotidase, etc. The current review presents a compilation of important plant secondary metabolites that are effective against snake venom due to enzyme neutralization.

• Journal of Home Health Care Nursing
• /
• v.21 no.2
• /
• pp.110-119
• /
• 2014

Purpose: The objectives of this study were to identify interventions and to analyze the characteristics of headaches among hospitalized patients with subarachnoid hemorrhage with moderate or severe headaches. Methods: A retrospective review of the electronic medical records of 210 patients who received treatment for subarachnoid hemorrhage was conducted. Data collection was done using a structured headache record sheet. Data analysis was carried out using the PASW 18.0 version program. Results: There were significant differences in number and duration of headaches of headaches according to the presence of vasospasm, increased intracranial pressure, extraventricular drainage, use of hypertonic solution, and hospitalization period (p<0.05). Patients with vasospasm and extraventricular drainage experienced the most severe headache for a duration of 3 to 7 days. Other patients experienced the most severe headache for around 1-2 days. Conclusion: Hospitalized patients with subarachnoid hemorrhage who had vasospasms experienced more headaches and the duration of these headaches were longer. In particular, the assessment and interventions for headaches should increase and be carried out actively during this time because the intensity of these headaches is severe and lasts for 3-7 days. Additionally, we emphasize the need for regular administration of analgesics in order to promote patients' well-being. On the basis of the results of this study,we suggest that evidence-based interventions for the care of headaches among hospitalized patients with subarachnoid hemorrhage should be developed.

• The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
• /
• v.30 no.2
• /
• pp.1-18
• /
• 2017

Objectives : This review aims to evaluate a risk of bias by risk of bias tool and RoBANS(Risk of Bias Assessment tool for Non-randomized Study) tool for clinical trial papers proving treatment effect of Korean medicines to alopecia and provides the newest reason of effectiveness of herbs to alopecia. Methods : Data were collected through electronic database including NDSL, KISS, KMBASE, Koreantk, OASIS, KoreaMed, KISTI, Pubmed, Cochrane CENTRAL and CINAHL. Two experts in Oriental Medicine assessed risk of bias of randomized controlled trials by Cochrane group's Risk of Bias tool and non-randomized controlled trials by RoBANS tool after searching, reviewing and selecting papers. Results : Total number of selected trials is 20 including 4 randomized controlled trial, 13 non-randomized controlled trials and 3 case reports. This study evaluate the risk of bias of 17 papers including 4 randomized controlled trials and 13 non-randomized controlled trials except 3 case reports by risk of bias tool and RoBANS tool. All papers of randomized controlled trials are evaluated unclear for random sequence generation and allocation concealment as there are no word on them. And all papers of non-randomized controlled trials are evaluated unclear for blinding of outcome assessments and relatively low for others. Conclusions : Korean medicine intervention can be an effective for treatment in alopecia. It was evaluated by hair density, thickness and expert panel assessment of photographs and all results are statistically significant. But enhancing levels of evidence, we must try to reduce bias in researches and report a safety, protocol and IRB.

• The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
• /
• v.30 no.3
• /
• pp.1-19
• /
• 2017

Objectives : This study aimed to validate the effect of herbal medicine intervention to relieve the symptoms of psoriasis using systematic review and meta-analysis and provide the newest reason of effectiveness of Korean medicine to psoriasis. Methods : Data were collected through electronic database including Pubmed, Cochrane CENTRAL, NDSL OASIS, Koreantk. Two experts assessed risk of bias of randomized controlled trials by Cochrane group's Risk of Bias tool after searching, reviewing and selecting papers. Data were analyzed using Review Manager(RevMan) 5.3 and Comprehensive Meta Analysis 2.0. Results : Total number of selected trials was 16 randomized controlled trials. This study evaluated the risk of bias and effectiveness of herbal medicine to psoriasis. There were high frequency uncertain in selection bias, performance bias and detection bias. In this meta-analysis, Korean medicine treatment was more effective than western medicine (ES:0.507, 95%CI:0.147-0.867) and placebo (ES:0.955, 95%CI:0.598-1.312). Conclusions : Herbal medicine intervention can be an effective for treatment in psoriasis. But enhancing levels of evidence, we must try to accumulate clinical researches of herbal medicine to psoriasis in Korea.

• Proceedings of the KSR Conference
• /
• 2009.05a
• /
• pp.396-405
• /
• 2009

An interlocking equipment of railway signalling systems should have very high functional safety and reliability properties because of its vital railway protection functionality. In order to achieve the required safety and reliability level, an engineer, in general, designs and implements the interlocking equipment to operate under RTOS(Realtime Operating System) environment, and the control hardware architecture redundant to cope with the random failures of system or subsystem. In such an architecture, it's very difficult to implement the interlocking equipment to communicate with various interface systems including the signal operator's terminal. In this paper, we propose a dual ethernet network topology and dual packet seamless transfer protocol algorithm for railway signaling system such as the interlocking equipment. We verify in this paper that the proposed DPST protocol algorithm has the evidence of its robust properties against the random hardware faults and communication errors. The proposed communication structure and algorithm is implemented in the electronic interlocking equipment for the private railway system of Hyundai Steel Company and its performance and properties are validated on the guideline of European Railway Standard EN50159.

• Bulletin of the Korean Chemical Society
• /
• v.35 no.2
• /
• pp.436-440
• /
• 2014

The ${\alpha}$-Effect; Ground state; Transition state; Intramolecular H-bonding; Yukawa-Tsuno plot; Second-order rate constants for aminolysis of 2-chloro-4-nitrophenyl X-substituted-benzoates (1a-h) have been measured spectrophotometrically in 80 mol % $H_2O/20$ mol % DMSO at $25.0^{\circ}C$. The Br${\emptyset}$nsted-type plot for the reactions of 2-chloro-4-nitrophenyl benzoate (1d) with a series of primary amines curves downward, which has been taken as evidence for a stepwise mechanism with a change in rate-determining step (RDS). The Hammett plots for the reactions of 1a-h with hydrazine and glycylglycine are nonlinear while the Yukawa-Tsuno plots exhibit excellent linearity with ${\rho}_X=1.22-1.35$ and ${\gamma}= 0.57-0.59$, indicating that the nonlinear Hammett plots are not due to a change in RDS but are caused by stabilization of substrates possessing an electron-donating group (EDG) through resonance interactions between the EDG and C=O bond of the substrates. The ${\alpha}$-effect exhibited by hydrazine increases as the substituent X changes from a strong EDG to a strong electron-withdrawing group (EWG). It has been concluded that destabilization of hydrazine through the electronic repulsion between the adjacent nonbonding electrons is not solely responsible for the substituent dependent ${\alpha}$-effect but stabilization of the transition state is also a plausible origin of the ${\alpha}$-effect.

• Journal of Korean Physical Therapy Science
• /
• v.15 no.3
• /
• pp.73-79
• /
• 2008

Background : Treadmill training has been proposed as a useful adjunct to conventional physical therapy to restore ability to walk after stroke. The purpose of this study to inform clinical practise by evaluating the research evidence for the effectiveness of treadmill training after stroke. Methods : We searched to the effectiveness of any form of intervention for effect of treadmill training by Dankook University electronic library databases of Medline, Embase, Cinahl, Amed and PEDro combined with a hand search of papers published in relevant peer-reviewed journals. Any type of study relevant to the topic published in English during time period from 1980 to 2007 was included. Results : The literature search identified 35 studies. The included studies enrolled a total of 374 subjects. 1. Treadmill retraining without partial body weight support might be more effective than no treatment at improving gait velocity, get up and go time, gait endurance and step length symmetry. 2. Treadmill retraining with partial body weight support might be more effective than no treatment in improving step length symmetry, gait velocity, gait endurance and balance. 3. Treadmill retraining might be more effective with partial body weight support than without it at improving gait velocity and motor improvement as measured by The Stroke Rehabilitation Assessment of Movement(STREAM). 4. Treadmill retraining without partial body weight support may be no different from physiotherapy and increase gait velocity to conventional gait therapy. 5. Treadmill retraining with partial body weight support may be no different from physiotherapy for gait velocity, motor recovery and balance. Conclusion The review suggests that although treadmill training of gait, especially with partial body weight support, might Improve gait parameters and functional mobility, unless treadmill training is directed at Improving gait speed it might be no more effective than conventional physical therapy at improving gait parameters.

• Perspectives in Nursing Science
• /
• v.10 no.1
• /
• pp.65-76
• /
• 2013

Purpose: To identify an associations between health care workers' uniforms and health care-associated infection. Methods: Electronic databases, including Ovid-Medline, the Cochrane Library, CINAHL, EMBASE, KMbase, and KoreaMed, were searched. The search terms included doctor, nurse, health care worker/staff/assistant, clothing, (white) gown, uniform, (neck)tie, and attire. Only papers published in English and Korean were included. Results: 16 studies were selected from 1,900 references screened. All of the studies were non-comparative studies except for one. Four were conducted with doctors, six with nurses, one with health care workers including physiotherapists and one for medical staff plus visitors in a neonatal intensive care unit. Doctors more frequently changed their uniforms than neckties; therefore, the degree of contamination was more serious in neckties. The cuff zone was more likely to be heavily contaminated than other areas of long-sleeve gowns. Coats become contaminated quickly once worn, and colony counts reached a similar level within the first few hours after wearing them. Wearing a plastic apron or protective clothing did not prevent the bacterial contamination of nurses' uniforms, and the best way to decrease the contamination was changing to newly laundered uniforms before starting every duty. Conclusion: Healthcare workers' uniforms are a potential source of health care-associated infection although there was no robust evidence. The government must establish standards for laundering of uniforms or a requirement for institutions to provide a laundering service for healthcare workers' uniforms.

• Proceedings of the Korea Association of Information Systems Conference
• /
• 2004.11a
• /
• pp.201-208
• /
• 2004

Many organizations experience that the Performance they gained from IT portfolio is lower than they expected values. As with any investment, executives are concerned with maximizing the performance from their investment in IT. This study focused on the relationship or fit between orientations of IT strategy and directions of IT portfolio to maximize IT performance. A field survey of chief information officers of Korea manufacturing sector was conducted in 2003. Complete data of 147 firms was analyzed to determine relationship among the three research constructs that are orientations of IT strategy, directions IT portfolio, and IT performance. In this study, the orientations of IT strategy have two dimensions that are operation orientation and market orientation. The directions of IT portfolio have two dimension that are internal system focused and external system focused. And the IT performance has divided into operational performance and competitive performance. As a result of this study, the companies that are putting a focus with operation orientation were concentrated on internal information systems than external information systems. On the other hand, the other companies that are focused on market orientation were concentrated on external information systems than internal information systems. Consequently, the companies that are focused on operation orientation were operational performance higher than competitive performance and the other companies that are focused on market orientation were competitive performance higher than operational performance. More importantly, the research results provide empirical evidence that supports the hypothesis related to closer fit between IT strategy and IT portfolio does lead to increase operational and competitive performance of IT. And the results emphasize manager's efforts of fit between orientations of IT strategy and directions of IT portfolio to be realized IT performance.