• Bulletin of the Korean Chemical Society
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• v.26 no.11
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• pp.1819-1822
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• 2005

In the search for a simple preparation method of heterogeneous catalyst, the iron porphyrins were coordinated bonded to the surface of a polymeric core-shell nanosphere. The heterogeneous catalyst was characterized by FT-IR, scanning electron microscope, and UV-vis spectrophotometer. The iron porphyrin bound core-shell nanospheres was about 470 nm in diameter and their catalytic activity for cyclohexene oxidation was similar to a homogeneous iron porphyrin in a solvent composition range of 25-75% acetonitrile/water (v/v). In addition, they could be recovered by simple centrifugation and their catalytic activity was maintained more than the third cycle.

• 제어로봇시스템학회:학술대회논문집
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• 2001.10a
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• pp.127.6-127
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• 2001

In this paper, we deal with two bias compensation algorithms of acceleration sensor for measuring the galloping on power transmission line. Firstly, the block diagram of galloping measurement system is given and a galloping model is presented. Secondly, two compensation algorithms, a simple compensation and a period compensation, are proposed. A simple compensation algorithm use the drafts of velocity and distance at fixed periods, so it is useful for constant bias case. Next, a period compensation algorithm can compensate a periodic bias. This algorithm use the previous measured data and compensated data for constant period, where the period is obtained by FFT method. Lastly, the effectiveness of proposed algorithms is verified by comparing between two algorithms in simulation, and its characteristics and the bias error bound are shown, respectively.

• Journal of Advanced Marine Engineering and Technology
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• v.27 no.7
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• pp.914-920
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• 2003

In this paper, we deal with two drift compensation algorithms of acceleration sensor for measuring the galloping on power transmission line. Firstly, the block diagram of galloping measurement system is given and a galloping model is presented. Secondly, two compensation algorithms, a simple compensation and a period compensation, are proposed. A simple compensation algorithm uses the drifts of velocity and distance at fixed periods, so it is useful for constant drift case. Next, a period compensation algorithm can compensate a periodic drift. This algorithm uses the previous measured data and compensated data for constant period, where the period is obtained by FFT method. Lastly, the effectiveness of proposed algorithms is verified by comparing between two algorithms in simulation, and its characteristics and the drift error bound are shown, respectively.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.34 no.11C
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• pp.1025-1028
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• 2009

This paper presents upper bounds of Maximum Likelihood (ML) decoding performance of a few irregular LDPC codes using the simple bound and ML input output weight distributions and it is shown that contrary to general opinion that as block length becomes longer, BP decoding performance becomes simply closer to ML decoding performance, before peak degradation, as block length becomes longer, BP decoding performance falls behind ML decoding performance more and after peak degradation, general opinion holds.

• International conference on construction engineering and project management
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• 2015.10a
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• pp.259-262
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• 2015

Due to the labor-intensiveness, high investment cost, long execution time, frequent change orders, and many stakeholders in a BIM project, a BIM manager is bound to face a lot of risks to make decisions in cost managing process. Since the productivity of a BIM team will affect the execution cost, this study investigates a simple method of assessing the productivity of a BIM team using the working timesheet records of the team. In this research, the productivity of a BIM team is defined as the effective working floor area (in square meters) of BIM uses per labor-time (in man-months) spent by the team. After the applicability of this method is tested by regression analysis using data from 5 real BIM projects in the construction phase, it is found that the simple productivity definition adopted in the method, although easy-to-implement, does not produce a statistically constant productivity value. More research is therefore needed in the future to devise better indicator(s) for assessing the productivity of a BIM team.

• Bulletin of the Korean Chemical Society
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• v.25 no.10
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• pp.1477-1483
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• 2004

We present the tandem mass spectrometry applications carried out to elucidate the coordination structure of Zn(II) bound lysine ternary complexes, $(Zn+Lys+Lys-H)^+$, which is a good model system to represent a simple (metallo)enzyme-substrate complex (ES). In particular, experimental efforts were focused on revealing the involvement of a lysine side chain ${\varepsilon}$-amino group in the coordination of $Zn^{2+}$ divalent ions. MS/MS fragmentation pattern showed that all the oxygen species within a complex fell off in the form of $H_2O$ in contrast to those of other ternary complexes containing amino acids with simple side chains (4-coordinate geometries, Figure 1a), suggesting that the lysine complexes have different coordination structures from the others. The participation of a lysine basic side chain in the coordination of Zn(II) was experimentally evidenced in MS/MS for $N{\varepsilon}$-Acetyl-L-Lys Zn(II) complexes with acetyl protection groups as well as in MS/MS for the ternary complexes with one $NH_3$ loss, $(Zn+Lys+Lys-NH_3-H)^+$. Detailed structures were predicted using ab initio calculations on $(Zn+Lys+Lys-H)^+$ isomers with 4-, 5-, and 6-coordinate structures. A zwitterionic 4-coordinate complex (Figure 7d) and a 5-coordinate structure with distorted bipyramidal geometry (Figure 7b) are found to be most plausible in terms of energy stability and compatibility with the experimental observations, respectively.

• Bulletin of the Korean Chemical Society
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• v.16 no.12
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• pp.1193-1203
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• 1995

In this work, we focused on the setup of the tools for the analysis of the final rotational state distribution of photofragments in vibrational predissociations of triatomic van der Waals molecules A-B2. We found that reflection principle used for the direct photodissociation processes can also be applied to find out the final rotational state distributions for indirect photodissociation processes. The quantity which represents the strength of rovibrational coupling between the quasi-bound state and the final state is reflected into the mirror of the classical angular momentum function, instead of the initial state before light absorption used in the reflection principle of direct processes. The sign change in the first derivative of the interaction potential with respect to the bond distance of B2 is found to be the source of the binodal structures in the final rotational distributions of photofragments in the model system studied in this work. In MQDT analysis, short range eigenchannel basis functions were found to be localized in angle, in the previous work [Lee, C.W. Bull. Korean Chem. Soc. 1995, 16, 957.] and may be called angle functions. Angle functions enjoy simple geometrical structures which have simple functional relations with the final state distributions of photofragments. Two processes take place along the angle functions which resemble the quasi-bound state and dominate over other processes. Two such angle functions are found to be not only localized angularly but also localized either one of ends of B2 in motions along the bond of B2. These dominating photodissociation processes, however, cancel each other. This cancellation causes photodissociation to depend sensitively on the interaction potential at other angles than the dominant one. Part of potential surface where much larger torque exists can now play an important role in photodissociation. MQDT also enables us to see which processes play important roles after cancellation. This is done by examining the amounts of time delayed by asymptotic eigenchannels.

• Coupled systems mechanics
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• v.7 no.5
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• pp.509-524
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• 2018

A hierarchical multi-scale modeling strategy devoted to the study of a Bitumen-Bound Gravel (BBG) is presented in this paper. More precisely, the paper investigates the temperature-dependent linear viscoelastic of the material when submitted to low deformations levels and moderate number of cycles. In such a hierarchical approach, 3D digital Representative Elementary Volumes are built and the outcomes at a scale (here, the sub-mesoscale) are used as input data at the next higher scale (here, the mesoscale). The viscoelastic behavior of the bituminous phases at each scale is taken into account by means of a generalized Maxwell model: the bulk part of the behavior is separated from the deviatoric one and bulk and shear moduli are expanded into Prony series. Furthermore, the viscoelastic phases are considered to be thermorheologically simple: time and temperature are not independent. This behavior is reproduced by the Williams-Landel-Ferry law. By means of the FE simulations of stress relaxation tests, the parameters of the various features of this temperature-dependent viscoelastic behavior are identified.

• Industrial Engineering and Management Systems
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• v.12 no.1
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• pp.51-62
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• 2013

This paper considers a single machine rescheduling problem whose original (efficiency related) objective is minimizing makespan. We assume that disruptions such as order cancelations and newly arrived orders occur after the initial scheduling, and we reschedule this disrupted schedule with the objective of minimizing a disruption related objective while preserving the original objective. The disruption related objective measures the impact of the disruptions as difference of completion times in the remaining (uncanceled) jobs before and after the disruptions. The artificial due dates for the remaining jobs are set to completion times in the original schedule while newly arrived jobs do not have due dates. Then, the objective of the rescheduling is minimizing the maximum earliness without tardiness. In order to preserve the optimality of the original objective, we assume that no-idle time and no tardiness are allowed while rescheduling. We first define this new problem and prove that the general version of the problem is unary NP-complete. Then, we develop three simple but intuitive heuristics. For each of the three heuristics, we find a tight bound on the measure called modified z-approximation ratio. The best theoretical bound is found to be 0.5 - ${\varepsilon}$ for some ${\varepsilon}$ > 0, and it implies that the solution value of the best heuristic is at most around a half of the worst possible solution value. Finally, we empirically evaluate the heuristics and demonstrate that the two best heuristics perform much better than the other one.

• Applied Biological Chemistry
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• v.27 no.1
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• pp.1-6
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• 1984

The lipoprotein-bound carotenoids occurred in the viscera of abalone (Haliotis discus hannai) were separated and characterized to be the mixture of fatty acid esters of lutein and free lutein. The main fatty acid components of the esters were lauric (68%) and myristic acid (17%), and indicated the characteristic pattern compared with that of triglycerides and cholesterol esters in abalone. Patterns of carotenoids from the lipoproteins were, simple and this suggested selected metabolisms of various feed-originated carotenoids found in the whole acetone extract of abalone.